51264556240 has 40 divisors (see below), whose sum is σ = 119921351328. Its totient is φ = 20380014720.

The previous prime is 51264556219. The next prime is 51264556247. The reversal of 51264556240 is 4265546215.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (40) 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 (40).

It is a junction number, because it is equal to n+sod(n) for n = 51264556193 and 51264556202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51264556247) 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, 1952626 + ... + 1978705.

Almost surely, 2^51264556240 is an apocalyptic number.

It is an amenable number.

51264556240 is an abundant number, since it is smaller than the sum of its proper divisors (68656795088).

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

51264556240 is a wasteful number, since it uses less digits than its factorization.

51264556240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3931507 (or 3931501 counting only the distinct ones).

The product of its (nonzero) digits is 288000, while the sum is 40.

The spelling of 51264556240 in words is "fifty-one billion, two hundred sixty-four million, five hundred fifty-six thousand, two hundred forty".