21415470440 has 192 divisors, whose sum is σ = 60762441600. Its totient is φ = 6648984576.

The previous prime is 21415470409. The next prime is 21415470449. The reversal of 21415470440 is 4407451412.

It is a junction number, because it is equal to n+sod(n) for n = 21415470397 and 21415470406.

It is not an unprimeable number, because it can be changed into a prime (21415470449) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2503691 + ... + 2512229.

It is an arithmetic number, because the mean of its divisors is an integer number (316471050).

Almost surely, 2^21415470440 is an apocalyptic number.

21415470440 is a gapful number since it is divisible by the number (20) 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 21415470440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30381220800).

21415470440 is an abundant number, since it is smaller than the sum of its proper divisors (39346971160).

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

21415470440 is a wasteful number, since it uses less digits than its factorization.

21415470440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8636 (or 8619 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 32.

The spelling of 21415470440 in words is "twenty-one billion, four hundred fifteen million, four hundred seventy thousand, four hundred forty".