21144031998 has 32 divisors (see below), whose sum is σ = 42449383680. Its totient is φ = 7021175040.

The previous prime is 21144031973. The next prime is 21144032023. The reversal of 21144031998 is 89913044112.

It is an interprime number because it is at equal distance from previous prime (21144031973) and next prime (21144032023).

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, 1814286 + ... + 1825902.

It is an arithmetic number, because the mean of its divisors is an integer number (1326543240).

Almost surely, 2^21144031998 is an apocalyptic number.

21144031998 is an abundant number, since it is smaller than the sum of its proper divisors (21305351682).

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

21144031998 is a wasteful number, since it uses less digits than its factorization.

21144031998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12752.

The product of its (nonzero) digits is 62208, while the sum is 42.

The spelling of 21144031998 in words is "twenty-one billion, one hundred forty-four million, thirty-one thousand, nine hundred ninety-eight".