21865846492 has 12 divisors (see below), whose sum is σ = 43731693040. Its totient is φ = 9371077056.

The previous prime is 21865846477. The next prime is 21865846543. The reversal of 21865846492 is 29464856812.

21865846492 is an admirable number.

It is a hoax number, since the sum of its digits (55) coincides with the sum of the digits of its distinct prime factors.

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 3 ways as a sum of consecutive naturals, for example, 390461517 + ... + 390461572.

Almost surely, 2^21865846492 is an apocalyptic number.

It is an amenable number.

21865846492 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21865846492 is a wasteful number, since it uses less digits than its factorization.

21865846492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780923100 (or 780923098 counting only the distinct ones).

The product of its digits is 6635520, while the sum is 55.

The spelling of 21865846492 in words is "twenty-one billion, eight hundred sixty-five million, eight hundred forty-six thousand, four hundred ninety-two".