21827817984 has 80 divisors (see below), whose sum is σ = 66457942848. Its totient is φ = 6236516352.

The previous prime is 21827817983. The next prime is 21827818009. The reversal of 21827817984 is 48971872812.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21827817983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1004307 + ... + 1025810.

Almost surely, 2^21827817984 is an apocalyptic number.

21827817984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21827817984 is an abundant number, since it is smaller than the sum of its proper divisors (44630124864).

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

21827817984 is an equidigital number, since it uses as much as digits as its factorization.

21827817984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2030145 (or 2030129 counting only the distinct ones).

The product of its digits is 3612672, while the sum is 57.

The spelling of 21827817984 in words is "twenty-one billion, eight hundred twenty-seven million, eight hundred seventeen thousand, nine hundred eighty-four".