21872630789 has 2 divisors, whose sum is σ = 21872630790. Its totient is φ = 21872630788.

The previous prime is 21872630761. The next prime is 21872630839. The reversal of 21872630789 is 98703627812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14136021025 + 7736609764 = 118895^2 + 87958^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21872630789 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21872630789.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21872690789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10936315394 + 10936315395.

It is an arithmetic number, because the mean of its divisors is an integer number (10936315395).

Almost surely, 2^21872630789 is an apocalyptic number.

It is an amenable number.

21872630789 is a deficient number, since it is larger than the sum of its proper divisors (1).

21872630789 is an equidigital number, since it uses as much as digits as its factorization.

21872630789 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2032128, while the sum is 53.

The spelling of 21872630789 in words is "twenty-one billion, eight hundred seventy-two million, six hundred thirty thousand, seven hundred eighty-nine".