51696440 has 32 divisors (see below), whose sum is σ = 116532000. Its totient is φ = 20640384.

The previous prime is 51696431. The next prime is 51696443. The reversal of 51696440 is 4469615.

51696440 = 1790² + 1791² + ... + 1805².

It is a self number, because there is not a number n which added to its sum of digits gives 51696440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51696443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32381 + ... + 33939.

It is an arithmetic number, because the mean of its divisors is an integer number (3641625).

Almost surely, 2^51696440 is an apocalyptic number.

It is an amenable number.

51696440 is an abundant number, since it is smaller than the sum of its proper divisors (64835560).

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

51696440 is a wasteful number, since it uses less digits than its factorization.

51696440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2399 (or 2395 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 51696440 is about 7190.0236439111. The cubic root of 51696440 is about 372.5233893696.

The spelling of 51696440 in words is "fifty-one million, six hundred ninety-six thousand, four hundred forty".