21297799545984 has 1280 divisors, whose sum is σ = 74062189555200. Its totient is φ = 6020858511360.

The previous prime is 21297799545959. The next prime is 21297799545991. The reversal of 21297799545984 is 48954599779212.

21297799545984 is a `hidden beast` number, since 2 + 1 + 2 + 9 + 7 + 79 + 95 + 459 + 8 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 21666123157 + ... + 21666124139.

It is an arithmetic number, because the mean of its divisors is an integer number (57861085590).

Almost surely, 2^{21297799545984} is an apocalyptic number.

21297799545984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21297799545984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37031094777600).

21297799545984 is an abundant number, since it is smaller than the sum of its proper divisors (52764390009216).

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

21297799545984 is a wasteful number, since it uses less digits than its factorization.

21297799545984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1315 (or 1294 counting only the distinct ones).

The product of its digits is 4115059200, while the sum is 81.

The spelling of 21297799545984 in words is "twenty-one trillion, two hundred ninety-seven billion, seven hundred ninety-nine million, five hundred forty-five thousand, nine hundred eighty-four".