221427967 has 2 divisors, whose sum is σ = 221427968. Its totient is φ = 221427966.

The previous prime is 221427961. The next prime is 221427971. The reversal of 221427967 is 769724122.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221427967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221427961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110713983 + 110713984.

It is an arithmetic number, because the mean of its divisors is an integer number (110713984).

Almost surely, 2^221427967 is an apocalyptic number.

221427967 is a deficient number, since it is larger than the sum of its proper divisors (1).

221427967 is an equidigital number, since it uses as much as digits as its factorization.

221427967 is an evil number, because the sum of its binary digits is even.

The product of its digits is 84672, while the sum is 40.

The square root of 221427967 is about 14880.4558733931. The cubic root of 221427967 is about 604.9843740699.

The spelling of 221427967 in words is "two hundred twenty-one million, four hundred twenty-seven thousand, nine hundred sixty-seven".