21241209312 has 72 divisors (see below), whose sum is σ = 62641922616. Its totient is φ = 7080400512.

The previous prime is 21241209271. The next prime is 21241209337. The reversal of 21241209312 is 21390214212.

21241209312 is a `hidden beast` number, since 212 + 412 + 0 + 9 + 31 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1358043 + ... + 1373594.

It is an arithmetic number, because the mean of its divisors is an integer number (870026703).

Almost surely, 2^21241209312 is an apocalyptic number.

It is an amenable number.

21241209312 is an abundant number, since it is smaller than the sum of its proper divisors (41400713304).

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

21241209312 is an equidigital number, since it uses as much as digits as its factorization.

21241209312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2731662 (or 2731642 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The spelling of 21241209312 in words is "twenty-one billion, two hundred forty-one million, two hundred nine thousand, three hundred twelve".