869912621 has 4 divisors (see below), whose sum is σ = 891130044. Its totient is φ = 848695200.

The previous prime is 869912597. The next prime is 869912633. The reversal of 869912621 is 126219968.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 79459396 + 790453225 = 8914^2 + 28115^2 .

It is a cyclic number.

It is not a de Polignac number, because 869912621 - 2⁶ = 869912557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (869912651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10608650 + ... + 10608731.

It is an arithmetic number, because the mean of its divisors is an integer number (222782511).

Almost surely, 2^869912621 is an apocalyptic number.

It is an amenable number.

869912621 is a deficient number, since it is larger than the sum of its proper divisors (21217423).

869912621 is a wasteful number, since it uses less digits than its factorization.

869912621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21217422.

The product of its digits is 93312, while the sum is 44.

The square root of 869912621 is about 29494.2811575397. The cubic root of 869912621 is about 954.6083098996.

The spelling of 869912621 in words is "eight hundred sixty-nine million, nine hundred twelve thousand, six hundred twenty-one".