21392128852 has 12 divisors (see below), whose sum is σ = 37652621076. Its totient is φ = 10634237120.

The previous prime is 21392128847. The next prime is 21392128873. The reversal of 21392128852 is 25882129312.

It can be written as a sum of positive squares in 2 ways, for example, as 16590470416 + 4801658436 = 128804^2 + 69294^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21392128799 and 21392128808.

It is a congruent number.

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, 15456049 + ... + 15457432.

It is an arithmetic number, because the mean of its divisors is an integer number (3137718423).

Almost surely, 2^21392128852 is an apocalyptic number.

It is an amenable number.

21392128852 is a deficient number, since it is larger than the sum of its proper divisors (16260492224).

21392128852 is a wasteful number, since it uses less digits than its factorization.

21392128852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30913658 (or 30913656 counting only the distinct ones).

The product of its digits is 138240, while the sum is 43.

The spelling of 21392128852 in words is "twenty-one billion, three hundred ninety-two million, one hundred twenty-eight thousand, eight hundred fifty-two".