21453753990 has 32 divisors (see below), whose sum is σ = 51944672736. Its totient is φ = 5670371840.

The previous prime is 21453753989. The next prime is 21453754033. The reversal of 21453753990 is 9935735412.

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, 3160881 + ... + 3167660.

It is an arithmetic number, because the mean of its divisors is an integer number (1623271023).

Almost surely, 2^21453753990 is an apocalyptic number.

21453753990 is an abundant number, since it is smaller than the sum of its proper divisors (30490918746).

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

21453753990 is a wasteful number, since it uses less digits than its factorization.

21453753990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6328664.

The product of its (nonzero) digits is 1020600, while the sum is 48.

The spelling of 21453753990 in words is "twenty-one billion, four hundred fifty-three million, seven hundred fifty-three thousand, nine hundred ninety".