872136921 has 8 divisors (see below), whose sum is σ = 1163025760. Its totient is φ = 581336352.

The previous prime is 872136901. The next prime is 872136971. The reversal of 872136921 is 129631278.

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

It is not a de Polignac number, because 872136921 - 2¹⁴ = 872120537 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 872136921.

It is not an unprimeable number, because it can be changed into a prime (872136901) 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, 6141 + ... + 42213.

It is an arithmetic number, because the mean of its divisors is an integer number (145378220).

Almost surely, 2^872136921 is an apocalyptic number.

It is an amenable number.

872136921 is a deficient number, since it is larger than the sum of its proper divisors (290888839).

872136921 is a wasteful number, since it uses less digits than its factorization.

872136921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44135.

The product of its digits is 36288, while the sum is 39.

The square root of 872136921 is about 29531.9643945336. The cubic root of 872136921 is about 955.4212375598.

The spelling of 872136921 in words is "eight hundred seventy-two million, one hundred thirty-six thousand, nine hundred twenty-one".