21641190540 has 48 divisors (see below), whose sum is σ = 60688238688. Its totient is φ = 5762136064.

The previous prime is 21641190503. The next prime is 21641190541. The reversal of 21641190540 is 4509114612.

It is a super-2 number, since 2×21641190540² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21641190541) 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, 236997 + ... + 315356.

It is an arithmetic number, because the mean of its divisors is an integer number (1264338306).

Almost surely, 2^21641190540 is an apocalyptic number.

21641190540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21641190540 is an abundant number, since it is smaller than the sum of its proper divisors (39047048148).

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

21641190540 is a wasteful number, since it uses less digits than its factorization.

21641190540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 553018 (or 553016 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The spelling of 21641190540 in words is "twenty-one billion, six hundred forty-one million, one hundred ninety thousand, five hundred forty".