21158850291904 has 28 divisors (see below), whose sum is σ = 45216869976544. Its totient is φ = 9765623211264.

The previous prime is 21158850291899. The next prime is 21158850291923. The reversal of 21158850291904 is 40919205885112.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12715654392 + ... + 12715656055.

It is an arithmetic number, because the mean of its divisors is an integer number (1614888213448).

Almost surely, 2^{21158850291904} is an apocalyptic number.

It is an amenable number.

21158850291904 is an abundant number, since it is smaller than the sum of its proper divisors (24058019684640).

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

21158850291904 is a wasteful number, since it uses less digits than its factorization.

21158850291904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25431310472 (or 25431310462 counting only the distinct ones).

The product of its (nonzero) digits is 2073600, while the sum is 55.

The spelling of 21158850291904 in words is "twenty-one trillion, one hundred fifty-eight billion, eight hundred fifty million, two hundred ninety-one thousand, nine hundred four".