21623546662643 has 16 divisors (see below), whose sum is σ = 23314052361600. Its totient is φ = 19989227744640.

The previous prime is 21623546662631. The next prime is 21623546662693. The reversal of 21623546662643 is 34626664532612.

It is a cyclic number.

It is not a de Polignac number, because 21623546662643 - 2³² = 21619251695347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21623546662603) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12291113 + ... + 13939818.

It is an arithmetic number, because the mean of its divisors is an integer number (1457128272600).

Almost surely, 2^{21623546662643} is an apocalyptic number.

21623546662643 is a deficient number, since it is larger than the sum of its proper divisors (1690505698957).

21623546662643 is a wasteful number, since it uses less digits than its factorization.

21623546662643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26232002.

The product of its digits is 44789760, while the sum is 56.

The spelling of 21623546662643 in words is "twenty-one trillion, six hundred twenty-three billion, five hundred forty-six million, six hundred sixty-two thousand, six hundred forty-three".