21623061644 has 24 divisors (see below), whose sum is σ = 40392979200. Its totient is φ = 10098239760.

The previous prime is 21623061643. The next prime is 21623061697. The reversal of 21623061644 is 44616032612.

It is a super-3 number, since 3×21623061644³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21623061643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1998224 + ... + 2009015.

It is an arithmetic number, because the mean of its divisors is an integer number (1683040800).

Almost surely, 2^21623061644 is an apocalyptic number.

It is an amenable number.

21623061644 is a deficient number, since it is larger than the sum of its proper divisors (18769917556).

21623061644 is a wasteful number, since it uses less digits than its factorization.

21623061644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4007333 (or 4007331 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 35.

The spelling of 21623061644 in words is "twenty-one billion, six hundred twenty-three million, sixty-one thousand, six hundred forty-four".