220642691 has 2 divisors, whose sum is σ = 220642692. Its totient is φ = 220642690.

The previous prime is 220642663. The next prime is 220642727. The reversal of 220642691 is 196246022.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 220642691 - 2²⁶ = 153533827 is a prime.

It is a Chen prime.

It is equal to p_12155918 and since 220642691 and 12155918 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (220642601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110321345 + 110321346.

It is an arithmetic number, because the mean of its divisors is an integer number (110321346).

Almost surely, 2^220642691 is an apocalyptic number.

220642691 is a deficient number, since it is larger than the sum of its proper divisors (1).

220642691 is an equidigital number, since it uses as much as digits as its factorization.

220642691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 220642691 is about 14854.0462837572. The cubic root of 220642691 is about 604.2683512549.

The spelling of 220642691 in words is "two hundred twenty million, six hundred forty-two thousand, six hundred ninety-one".