21437942790840 has 64 divisors (see below), whose sum is σ = 66388468008960. Its totient is φ = 5532372332160.

The previous prime is 21437942790793. The next prime is 21437942790851. The reversal of 21437942790840 is 4809724973412.

It is a super-2 number, since 2×21437942790840² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2881440204 + ... + 2881447643.

It is an arithmetic number, because the mean of its divisors is an integer number (1037319812640).

Almost surely, 2^{21437942790840} is an apocalyptic number.

21437942790840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21437942790840 is an abundant number, since it is smaller than the sum of its proper divisors (44950525218120).

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

21437942790840 is a wasteful number, since it uses less digits than its factorization.

21437942790840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5762887892 (or 5762887888 counting only the distinct ones).

The product of its (nonzero) digits is 24385536, while the sum is 60.

The spelling of 21437942790840 in words is "twenty-one trillion, four hundred thirty-seven billion, nine hundred forty-two million, seven hundred ninety thousand, eight hundred forty".