21415315500 has 72 divisors (see below), whose sum is σ = 67558196160. Its totient is φ = 5710749600.

The previous prime is 21415315489. The next prime is 21415315501. The reversal of 21415315500 is 551351412.

21415315500 is a `hidden beast` number, since 2 + 1 + 4 + 153 + 1 + 5 + 500 = 666.

It is not an unprimeable number, because it can be changed into a prime (21415315501) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2374980 + ... + 2383979.

It is an arithmetic number, because the mean of its divisors is an integer number (938308280).

Almost surely, 2^21415315500 is an apocalyptic number.

21415315500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21415315500 is an abundant number, since it is smaller than the sum of its proper divisors (46142880660).

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

21415315500 is a wasteful number, since it uses less digits than its factorization.

21415315500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4758984 (or 4758969 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

Adding to 21415315500 its reverse (551351412), we get a palindrome (21966666912).

The spelling of 21415315500 in words is "twenty-one billion, four hundred fifteen million, three hundred fifteen thousand, five hundred".