51247949040 has 120 divisors (see below), whose sum is σ = 173059006848. Its totient is φ = 13590581760.

The previous prime is 51247949003. The next prime is 51247949047. The reversal of 51247949040 is 4094974215.

51247949040 is a `hidden beast` number, since 51 + 2 + 4 + 79 + 490 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51247949047) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 66304 + ... + 326943.

Almost surely, 2^51247949040 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 51247949040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86529503424).

51247949040 is an abundant number, since it is smaller than the sum of its proper divisors (121811057808).

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

51247949040 is a wasteful number, since it uses less digits than its factorization.

51247949040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393447 (or 393438 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The spelling of 51247949040 in words is "fifty-one billion, two hundred forty-seven million, nine hundred forty-nine thousand, forty".