21209381837392 has 80 divisors (see below), whose sum is σ = 47048110335360. Its totient is φ = 9073392966144.

The previous prime is 21209381837387. The next prime is 21209381837431. The reversal of 21209381837392 is 29373818390212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 244792383 + ... + 244879009.

It is an arithmetic number, because the mean of its divisors is an integer number (588101379192).

Almost surely, 2^{21209381837392} is an apocalyptic number.

It is an amenable number.

21209381837392 is an abundant number, since it is smaller than the sum of its proper divisors (25838728497968).

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

21209381837392 is a wasteful number, since it uses less digits than its factorization.

21209381837392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90548 (or 90542 counting only the distinct ones).

The product of its (nonzero) digits is 7838208, while the sum is 58.

The spelling of 21209381837392 in words is "twenty-one trillion, two hundred nine billion, three hundred eighty-one million, eight hundred thirty-seven thousand, three hundred ninety-two".