51901440 has 176 divisors, whose sum is σ = 172930560. Its totient is φ = 13271040.

The previous prime is 51901439. The next prime is 51901441. The reversal of 51901440 is 4410915.

It is an interprime number because it is at equal distance from previous prime (51901439) and next prime (51901441).

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 51901440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51901441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 476106 + ... + 476214.

It is an arithmetic number, because the mean of its divisors is an integer number (982560).

Almost surely, 2^51901440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51901440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86465280).

51901440 is an abundant number, since it is smaller than the sum of its proper divisors (121029120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51901440 is a wasteful number, since it uses less digits than its factorization.

51901440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 51901440 is about 7204.2654032177. The cubic root of 51901440 is about 373.0151483952.

The spelling of 51901440 in words is "fifty-one million, nine hundred one thousand, four hundred forty".