3128779925 has 6 divisors (see below), whose sum is σ = 3879687138. Its totient is φ = 2503023920.

The previous prime is 3128779921. The next prime is 3128779931. The reversal of 3128779925 is 5299778213.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 1957201 + 3126822724 = 1399^2 + 55918^2 .

It is not a de Polignac number, because 3128779925 - 2² = 3128779921 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3128779921) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 62575574 + ... + 62575623.

It is an arithmetic number, because the mean of its divisors is an integer number (646614523).

Almost surely, 2^3128779925 is an apocalyptic number.

It is an amenable number.

3128779925 is a deficient number, since it is larger than the sum of its proper divisors (750907213).

3128779925 is a wasteful number, since it uses less digits than its factorization.

3128779925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125151207 (or 125151202 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 53.

The square root of 3128779925 is about 55935.4978971315. The cubic root of 3128779925 is about 1462.5981018763.

The spelling of 3128779925 in words is "three billion, one hundred twenty-eight million, seven hundred seventy-nine thousand, nine hundred twenty-five".