21612111624452 has 6 divisors (see below), whose sum is σ = 37821195342798. Its totient is φ = 10806055812224.

The previous prime is 21612111624451. The next prime is 21612111624491. The reversal of 21612111624452 is 25442611121612.

It can be written as a sum of positive squares in only one way, i.e., 21387905586436 + 224206038016 = 4624706^2 + 473504^2 .

It is not an unprimeable number, because it can be changed into a prime (21612111624451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2701513953053 + ... + 2701513953060.

It is an arithmetic number, because the mean of its divisors is an integer number (6303532557133).

Almost surely, 2^{21612111624452} is an apocalyptic number.

It is an amenable number.

21612111624452 is a deficient number, since it is larger than the sum of its proper divisors (16209083718346).

21612111624452 is a wasteful number, since it uses less digits than its factorization.

21612111624452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5403027906117 (or 5403027906115 counting only the distinct ones).

The product of its digits is 46080, while the sum is 38.

The spelling of 21612111624452 in words is "twenty-one trillion, six hundred twelve billion, one hundred eleven million, six hundred twenty-four thousand, four hundred fifty-two".