21994572749520 has 240 divisors, whose sum is σ = 82240730006400. Its totient is φ = 4762734418944.

The previous prime is 21994572749519. The next prime is 21994572749557. The reversal of 21994572749520 is 2594727549912.

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-2 number, since 2×21994572749520² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 17526495 + ... + 18739454.

It is an arithmetic number, because the mean of its divisors is an integer number (342669708360).

Almost surely, 2^{21994572749520} is an apocalyptic number.

21994572749520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21994572749520 is an abundant number, since it is smaller than the sum of its proper divisors (60246157256880).

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

21994572749520 is a wasteful number, since it uses less digits than its factorization.

21994572749520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36266010 (or 36265985 counting only the distinct ones).

The product of its (nonzero) digits is 114307200, while the sum is 66.

The spelling of 21994572749520 in words is "twenty-one trillion, nine hundred ninety-four billion, five hundred seventy-two million, seven hundred forty-nine thousand, five hundred twenty".