221650646454491 has 2 divisors, whose sum is σ = 221650646454492. Its totient is φ = 221650646454490.

The previous prime is 221650646454427. The next prime is 221650646454553. The reversal of 221650646454491 is 194454646056122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221650646454491 - 2⁶ = 221650646454427 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221650646454491.

It is not a weakly prime, because it can be changed into another prime (221650646454091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110825323227245 + 110825323227246.

It is an arithmetic number, because the mean of its divisors is an integer number (110825323227246).

Almost surely, 2^{221650646454491} is an apocalyptic number.

221650646454491 is a deficient number, since it is larger than the sum of its proper divisors (1).

221650646454491 is an equidigital number, since it uses as much as digits as its factorization.

221650646454491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 49766400, while the sum is 59.

The spelling of 221650646454491 in words is "two hundred twenty-one trillion, six hundred fifty billion, six hundred forty-six million, four hundred fifty-four thousand, four hundred ninety-one".