21163944917740 has 48 divisors (see below), whose sum is σ = 46056529159200. Its totient is φ = 8159495565312.

The previous prime is 21163944917683. The next prime is 21163944917741. The reversal of 21163944917740 is 4771944936112.

It is a super-2 number, since 2×21163944917740² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (58).

It is not an unprimeable number, because it can be changed into a prime (21163944917741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31285410 + ... + 31954729.

It is an arithmetic number, because the mean of its divisors is an integer number (959511024150).

Almost surely, 2^{21163944917740} is an apocalyptic number.

21163944917740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21163944917740 is an abundant number, since it is smaller than the sum of its proper divisors (24892584241460).

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

21163944917740 is a wasteful number, since it uses less digits than its factorization.

21163944917740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63240754 (or 63240752 counting only the distinct ones).

The product of its (nonzero) digits is 9144576, while the sum is 58.

The spelling of 21163944917740 in words is "twenty-one trillion, one hundred sixty-three billion, nine hundred forty-four million, nine hundred seventeen thousand, seven hundred forty".