879517421 has 2 divisors, whose sum is σ = 879517422. Its totient is φ = 879517420.

The previous prime is 879517369. The next prime is 879517477. The reversal of 879517421 is 124715978.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 533148100 + 346369321 = 23090^2 + 18611^2 .

It is a cyclic number.

It is not a de Polignac number, because 879517421 - 2²² = 875323117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (879517921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 439758710 + 439758711.

It is an arithmetic number, because the mean of its divisors is an integer number (439758711).

Almost surely, 2^879517421 is an apocalyptic number.

It is an amenable number.

879517421 is a deficient number, since it is larger than the sum of its proper divisors (1).

879517421 is an equidigital number, since it uses as much as digits as its factorization.

879517421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 141120, while the sum is 44.

The square root of 879517421 is about 29656.6589655679. The cubic root of 879517421 is about 958.1087697915.

The spelling of 879517421 in words is "eight hundred seventy-nine million, five hundred seventeen thousand, four hundred twenty-one".