28130121064 has 16 divisors (see below), whose sum is σ = 53336607300. Its totient is φ = 13907025792.

The previous prime is 28130121059. The next prime is 28130121079. The reversal of 28130121064 is 46012103182.

It can be written as a sum of positive squares in 2 ways, for example, as 24914096964 + 3216024100 = 157842^2 + 56710^2 .

It is a super-2 number, since 2×28130121064² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19753587 + ... + 19755010.

Almost surely, 2^28130121064 is an apocalyptic number.

It is an amenable number.

28130121064 is a deficient number, since it is larger than the sum of its proper divisors (25206486236).

28130121064 is a wasteful number, since it uses less digits than its factorization.

28130121064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39508692 (or 39508688 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 28.

The spelling of 28130121064 in words is "twenty-eight billion, one hundred thirty million, one hundred twenty-one thousand, sixty-four".