21111997425024 has 256 divisors, whose sum is σ = 66355344840960. Its totient is φ = 5874386534400.

The previous prime is 21111997425017. The next prime is 21111997425059. The reversal of 21111997425024 is 42052479911112.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 641314 + ... + 6529569.

It is an arithmetic number, because the mean of its divisors is an integer number (259200565785).

Almost surely, 2^{21111997425024} is an apocalyptic number.

21111997425024 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 21111997425024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33177672420480).

21111997425024 is an abundant number, since it is smaller than the sum of its proper divisors (45243347415936).

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

21111997425024 is a wasteful number, since it uses less digits than its factorization.

21111997425024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7170969 (or 7170957 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 48.

The spelling of 21111997425024 in words is "twenty-one trillion, one hundred eleven billion, nine hundred ninety-seven million, four hundred twenty-five thousand, twenty-four".