921863881 has 8 divisors (see below), whose sum is σ = 928315584. Its totient is φ = 915423600.

The previous prime is 921863863. The next prime is 921863893. The reversal of 921863881 is 188368129.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 921863881 - 2⁷ = 921863753 is a prime.

It is a super-2 number, since 2×921863881² = 1699666030184764322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (921863381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 215146 + ... + 219388.

It is an arithmetic number, because the mean of its divisors is an integer number (116039448).

Almost surely, 2^921863881 is an apocalyptic number.

It is an amenable number.

921863881 is a deficient number, since it is larger than the sum of its proper divisors (6451703).

921863881 is a wasteful number, since it uses less digits than its factorization.

921863881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5711.

The product of its digits is 165888, while the sum is 46.

The square root of 921863881 is about 30362.2113983814. The cubic root of 921863881 is about 973.2451910733.

The spelling of 921863881 in words is "nine hundred twenty-one million, eight hundred sixty-three thousand, eight hundred eighty-one".