221958765647 has 2 divisors, whose sum is σ = 221958765648. Its totient is φ = 221958765646.

The previous prime is 221958765593. The next prime is 221958765661. The reversal of 221958765647 is 746567859122.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221958765647 - 2⁶ = 221958765583 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221958765647.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221958765247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110979382823 + 110979382824.

It is an arithmetic number, because the mean of its divisors is an integer number (110979382824).

Almost surely, 2^221958765647 is an apocalyptic number.

221958765647 is a deficient number, since it is larger than the sum of its proper divisors (1).

221958765647 is an equidigital number, since it uses as much as digits as its factorization.

221958765647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50803200, while the sum is 62.

The spelling of 221958765647 in words is "two hundred twenty-one billion, nine hundred fifty-eight million, seven hundred sixty-five thousand, six hundred forty-seven".