21620132646 has 32 divisors (see below), whose sum is σ = 49477136640. Its totient is φ = 6169719456.

The previous prime is 21620132629. The next prime is 21620132647. The reversal of 21620132646 is 64623102612.

It is a super-2 number, since 2×21620132646² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21620132647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 275656 + ... + 345291.

It is an arithmetic number, because the mean of its divisors is an integer number (1546160520).

Almost surely, 2^21620132646 is an apocalyptic number.

21620132646 is an abundant number, since it is smaller than the sum of its proper divisors (27857003994).

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

21620132646 is a wasteful number, since it uses less digits than its factorization.

21620132646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 621788.

The product of its (nonzero) digits is 20736, while the sum is 33.

The spelling of 21620132646 in words is "twenty-one billion, six hundred twenty million, one hundred thirty-two thousand, six hundred forty-six".