21534427023720 has 128 divisors (see below), whose sum is σ = 69619559063040. Its totient is φ = 5297216716800.

The previous prime is 21534427023713. The next prime is 21534427023731. The reversal of 21534427023720 is 2732072443512.

It is a happy number.

It is a super-3 number, since 3×21534427023720³ (a number of 41 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2321881 + ... + 6961320.

It is an arithmetic number, because the mean of its divisors is an integer number (543902805180).

Almost surely, 2^{21534427023720} is an apocalyptic number.

21534427023720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21534427023720 is an abundant number, since it is smaller than the sum of its proper divisors (48085132039320).

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

21534427023720 is a wasteful number, since it uses less digits than its factorization.

21534427023720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9284715 (or 9284711 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 42.

The spelling of 21534427023720 in words is "twenty-one trillion, five hundred thirty-four billion, four hundred twenty-seven million, twenty-three thousand, seven hundred twenty".