652221991 has 2 divisors, whose sum is σ = 652221992. Its totient is φ = 652221990.

The previous prime is 652221959. The next prime is 652222013. The reversal of 652221991 is 199122256.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 652221991 - 2⁵ = 652221959 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 652221991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (652221901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 326110995 + 326110996.

It is an arithmetic number, because the mean of its divisors is an integer number (326110996).

Almost surely, 2^652221991 is an apocalyptic number.

652221991 is a deficient number, since it is larger than the sum of its proper divisors (1).

652221991 is an equidigital number, since it uses as much as digits as its factorization.

652221991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19440, while the sum is 37.

The square root of 652221991 is about 25538.6372189277. The cubic root of 652221991 is about 867.2250470863.

The spelling of 652221991 in words is "six hundred fifty-two million, two hundred twenty-one thousand, nine hundred ninety-one".