198926621 has 2 divisors, whose sum is σ = 198926622. Its totient is φ = 198926620.

The previous prime is 198926617. The next prime is 198926627. The reversal of 198926621 is 126629891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198415396 + 511225 = 14086^2 + 715^2 .

It is a cyclic number.

It is not a de Polignac number, because 198926621 - 2² = 198926617 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198926627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99463310 + 99463311.

It is an arithmetic number, because the mean of its divisors is an integer number (99463311).

Almost surely, 2^198926621 is an apocalyptic number.

It is an amenable number.

198926621 is a deficient number, since it is larger than the sum of its proper divisors (1).

198926621 is an equidigital number, since it uses as much as digits as its factorization.

198926621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93312, while the sum is 44.

The square root of 198926621 is about 14104.1348901661. The cubic root of 198926621 is about 583.7554773607.

The spelling of 198926621 in words is "one hundred ninety-eight million, nine hundred twenty-six thousand, six hundred twenty-one".