51393408 has 128 divisors (see below), whose sum is σ = 155692800. Its totient is φ = 14896640.

The previous prime is 51393389. The next prime is 51393409. The reversal of 51393408 is 80439315.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51393409) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2234485 + ... + 2234507.

It is an arithmetic number, because the mean of its divisors is an integer number (1216350).

Almost surely, 2^51393408 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 51393408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77846400).

51393408 is an abundant number, since it is smaller than the sum of its proper divisors (104299392).

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

51393408 is an equidigital number, since it uses as much as digits as its factorization.

51393408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97 (or 39 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 51393408 is about 7168.9195838704. The cubic root of 51393408 is about 371.7940818972.

The spelling of 51393408 in words is "fifty-one million, three hundred ninety-three thousand, four hundred eight".