199802621 has 2 divisors, whose sum is σ = 199802622. Its totient is φ = 199802620.

The previous prime is 199802599. The next prime is 199802699. The reversal of 199802621 is 126208991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 171976996 + 27825625 = 13114^2 + 5275^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199802621 is a prime.

It is a congruent number.

It is a weakly prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99901310 + 99901311.

It is an arithmetic number, because the mean of its divisors is an integer number (99901311).

Almost surely, 2^199802621 is an apocalyptic number.

It is an amenable number.

199802621 is a deficient number, since it is larger than the sum of its proper divisors (1).

199802621 is an equidigital number, since it uses as much as digits as its factorization.

199802621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 199802621 is about 14135.1554996753. The cubic root of 199802621 is about 584.6111044225.

The spelling of 199802621 in words is "one hundred ninety-nine million, eight hundred two thousand, six hundred twenty-one".