21612770642 has 16 divisors (see below), whose sum is σ = 32813206272. Its totient is φ = 10675775760.

The previous prime is 21612770611. The next prime is 21612770653. The reversal of 21612770642 is 24607721612.

It is a super-2 number, since 2×21612770642² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21612770596 and 21612770605.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126533 + ... + 243384.

It is an arithmetic number, because the mean of its divisors is an integer number (2050825392).

Almost surely, 2^21612770642 is an apocalyptic number.

21612770642 is a deficient number, since it is larger than the sum of its proper divisors (11200435630).

21612770642 is a wasteful number, since it uses less digits than its factorization.

21612770642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 370273.

The product of its (nonzero) digits is 56448, while the sum is 38.

The spelling of 21612770642 in words is "twenty-one billion, six hundred twelve million, seven hundred seventy thousand, six hundred forty-two".