21354315240 has 64 divisors (see below), whose sum is σ = 64552023360. Its totient is φ = 5651010560.

The previous prime is 21354315211. The next prime is 21354315253. The reversal of 21354315240 is 4251345312.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 21354315198 and 21354315207.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 663489 + ... + 694928.

It is an arithmetic number, because the mean of its divisors is an integer number (1008625365).

Almost surely, 2^21354315240 is an apocalyptic number.

21354315240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21354315240 is an abundant number, since it is smaller than the sum of its proper divisors (43197708120).

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

21354315240 is a wasteful number, since it uses less digits than its factorization.

21354315240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1358562 (or 1358558 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

The spelling of 21354315240 in words is "twenty-one billion, three hundred fifty-four million, three hundred fifteen thousand, two hundred forty".