51999988 has 6 divisors (see below), whose sum is σ = 90999986. Its totient is φ = 25999992.

The previous prime is 51999971. The next prime is 52000007. The reversal of 51999988 is 88999915.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 32126224 + 19873764 = 5668^2 + 4458^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6499995 + ... + 6500002.

Almost surely, 2^51999988 is an apocalyptic number.

It is an amenable number.

51999988 is a deficient number, since it is larger than the sum of its proper divisors (38999998).

51999988 is a wasteful number, since it uses less digits than its factorization.

51999988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13000001 (or 12999999 counting only the distinct ones).

The product of its digits is 2099520, while the sum is 58.

The square root of 51999988 is about 7211.1017188776. The cubic root of 51999988 is about 373.2510869701.

The spelling of 51999988 in words is "fifty-one million, nine hundred ninety-nine thousand, nine hundred eighty-eight".