872879621 has 2 divisors, whose sum is σ = 872879622. Its totient is φ = 872879620.

The previous prime is 872879599. The next prime is 872879633. The reversal of 872879621 is 126978278.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 845995396 + 26884225 = 29086^2 + 5185^2 .

It is a cyclic number.

It is not a de Polignac number, because 872879621 - 2¹⁰ = 872878597 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 872879621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (872879641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 436439810 + 436439811.

It is an arithmetic number, because the mean of its divisors is an integer number (436439811).

Almost surely, 2^872879621 is an apocalyptic number.

It is an amenable number.

872879621 is a deficient number, since it is larger than the sum of its proper divisors (1).

872879621 is an equidigital number, since it uses as much as digits as its factorization.

872879621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 677376, while the sum is 50.

The square root of 872879621 is about 29544.5362292252. The cubic root of 872879621 is about 955.6923685429.

The spelling of 872879621 in words is "eight hundred seventy-two million, eight hundred seventy-nine thousand, six hundred twenty-one".