51139908 has 36 divisors (see below), whose sum is σ = 130226460. Its totient is φ = 16920576.

The previous prime is 51139889. The next prime is 51139967. The reversal of 51139908 is 80993115.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 14197824 + 36942084 = 3768^2 + 6078^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 253 + ... + 10116.

Almost surely, 2^51139908 is an apocalyptic number.

It is an amenable number.

51139908 is an abundant number, since it is smaller than the sum of its proper divisors (79086552).

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

51139908 is a wasteful number, since it uses less digits than its factorization.

51139908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10516 (or 10511 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 51139908 is about 7151.2172390440. The cubic root of 51139908 is about 371.1817777575.

The spelling of 51139908 in words is "fifty-one million, one hundred thirty-nine thousand, nine hundred eight".