51287281240 has 32 divisors (see below), whose sum is σ = 124273028880. Its totient is φ = 18936842112.

The previous prime is 51287281187. The next prime is 51287281273. The reversal of 51287281240 is 4218278215.

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 = 51287281193 and 51287281202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49314174 + ... + 49315213.

Almost surely, 2^51287281240 is an apocalyptic number.

It is an amenable number.

51287281240 is an abundant number, since it is smaller than the sum of its proper divisors (72985747640).

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

51287281240 is a wasteful number, since it uses less digits than its factorization.

51287281240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98629411 (or 98629407 counting only the distinct ones).

The product of its (nonzero) digits is 71680, while the sum is 40.

The spelling of 51287281240 in words is "fifty-one billion, two hundred eighty-seven million, two hundred eighty-one thousand, two hundred forty".