21405225630 has 32 divisors (see below), whose sum is σ = 51525006624. Its totient is φ = 5691119616.

The previous prime is 21405225601. The next prime is 21405225659. The reversal of 21405225630 is 3652250412.

It is an interprime number because it is at equal distance from previous prime (21405225601) and next prime (21405225659).

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

It is a Curzon number.

It is a congruent number.

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, 1048507 + ... + 1068726.

It is an arithmetic number, because the mean of its divisors is an integer number (1610156457).

Almost surely, 2^21405225630 is an apocalyptic number.

21405225630 is an abundant number, since it is smaller than the sum of its proper divisors (30119780994).

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

21405225630 is a wasteful number, since it uses less digits than its factorization.

21405225630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2117580.

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

The spelling of 21405225630 in words is "twenty-one billion, four hundred five million, two hundred twenty-five thousand, six hundred thirty".