21472515636 has 96 divisors (see below), whose sum is σ = 59740574208. Its totient is φ = 5916620160.

The previous prime is 21472515629. The next prime is 21472515643. The reversal of 21472515636 is 63651527412.

It is an interprime number because it is at equal distance from previous prime (21472515629) and next prime (21472515643).

It is a super-2 number, since 2×21472515636² (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 31 ways as a sum of consecutive naturals, for example, 21591 + ... + 208353.

It is an arithmetic number, because the mean of its divisors is an integer number (622297648).

Almost surely, 2^21472515636 is an apocalyptic number.

21472515636 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21472515636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29870287104).

21472515636 is an abundant number, since it is smaller than the sum of its proper divisors (38268058572).

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

21472515636 is a wasteful number, since it uses less digits than its factorization.

21472515636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186861 (or 186859 counting only the distinct ones).

The product of its digits is 302400, while the sum is 42.

The spelling of 21472515636 in words is "twenty-one billion, four hundred seventy-two million, five hundred fifteen thousand, six hundred thirty-six".