51887990 has 64 divisors (see below), whose sum is σ = 118056960. Its totient is φ = 15949440.

The previous prime is 51887987. The next prime is 51887999. The reversal of 51887990 is 9978815.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51887999) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 60404 + ... + 61256.

It is an arithmetic number, because the mean of its divisors is an integer number (1844640).

Almost surely, 2^51887990 is an apocalyptic number.

51887990 is an abundant number, since it is smaller than the sum of its proper divisors (66168970).

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

51887990 is a wasteful number, since it uses less digits than its factorization.

51887990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 957.

The product of its (nonzero) digits is 181440, while the sum is 47.

The square root of 51887990 is about 7203.3318679622. The cubic root of 51887990 is about 372.9829239380.

The spelling of 51887990 in words is "fifty-one million, eight hundred eighty-seven thousand, nine hundred ninety".