20623436646 has 16 divisors (see below), whose sum is σ = 43417761600. Its totient is φ = 6512664168.

The previous prime is 20623436599. The next prime is 20623436671. The reversal of 20623436646 is 64663432602.

It is a super-2 number, since 2×20623436646² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20623436598 and 20623436607.

It is a congruent number.

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, 90453556 + ... + 90453783.

It is an arithmetic number, because the mean of its divisors is an integer number (2713610100).

Almost surely, 2^20623436646 is an apocalyptic number.

20623436646 is an abundant number, since it is smaller than the sum of its proper divisors (22794324954).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20623436646 is a wasteful number, since it uses less digits than its factorization.

20623436646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180907363.

The product of its (nonzero) digits is 746496, while the sum is 42.

The spelling of 20623436646 in words is "twenty billion, six hundred twenty-three million, four hundred thirty-six thousand, six hundred forty-six".