21415316420 has 24 divisors (see below), whose sum is σ = 44975202048. Its totient is φ = 8565548000.

The previous prime is 21415316401. The next prime is 21415316459. The reversal of 21415316420 is 2461351412.

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, 389645 + ... + 441195.

It is an arithmetic number, because the mean of its divisors is an integer number (1873966752).

Almost surely, 2^21415316420 is an apocalyptic number.

21415316420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21415316420 is an abundant number, since it is smaller than the sum of its proper divisors (23559885628).

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

21415316420 is a wasteful number, since it uses less digits than its factorization.

21415316420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72331 (or 72329 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

Adding to 21415316420 its reverse (2461351412), we get a palindrome (23876667832).

The spelling of 21415316420 in words is "twenty-one billion, four hundred fifteen million, three hundred sixteen thousand, four hundred twenty".