21301623021 has 16 divisors (see below), whose sum is σ = 33251315328. Its totient is φ = 11875468800.

The previous prime is 21301622977. The next prime is 21301623089. The reversal of 21301623021 is 12032610312.

It is not a de Polignac number, because 21301623021 - 2¹⁴ = 21301606637 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21301623821) 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, 12369420 + ... + 12371141.

It is an arithmetic number, because the mean of its divisors is an integer number (2078207208).

Almost surely, 2^21301623021 is an apocalyptic number.

21301623021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21301623021 is a deficient number, since it is larger than the sum of its proper divisors (11949692307).

21301623021 is a wasteful number, since it uses less digits than its factorization.

21301623021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24740612.

The product of its (nonzero) digits is 432, while the sum is 21.

The spelling of 21301623021 in words is "twenty-one billion, three hundred one million, six hundred twenty-three thousand, twenty-one".