102665621 has 2 divisors, whose sum is σ = 102665622. Its totient is φ = 102665620.

The previous prime is 102665609. The next prime is 102665653. The reversal of 102665621 is 126566201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71740900 + 30924721 = 8470^2 + 5561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-102665621 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102665671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51332810 + 51332811.

It is an arithmetic number, because the mean of its divisors is an integer number (51332811).

Almost surely, 2^102665621 is an apocalyptic number.

It is an amenable number.

102665621 is a deficient number, since it is larger than the sum of its proper divisors (1).

102665621 is an equidigital number, since it uses as much as digits as its factorization.

102665621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 102665621 is about 10132.4045023874. The cubic root of 102665621 is about 468.2470099493.

The spelling of 102665621 in words is "one hundred two million, six hundred sixty-five thousand, six hundred twenty-one".