20623436645 has 16 divisors (see below), whose sum is σ = 28365095808. Its totient is φ = 14101022400.

The previous prime is 20623436599. The next prime is 20623436671. The reversal of 20623436645 is 54663432602.

It is not a de Polignac number, because 20623436645 - 2¹⁰ = 20623435621 is a prime.

It is a super-2 number, since 2×20623436645² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 836906 + ... + 861195.

It is an arithmetic number, because the mean of its divisors is an integer number (1772818488).

Almost surely, 2^20623436645 is an apocalyptic number.

It is an amenable number.

20623436645 is a deficient number, since it is larger than the sum of its proper divisors (7741659163).

20623436645 is a wasteful number, since it uses less digits than its factorization.

20623436645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1698460.

The product of its (nonzero) digits is 622080, while the sum is 41.

The spelling of 20623436645 in words is "twenty billion, six hundred twenty-three million, four hundred thirty-six thousand, six hundred forty-five".