18880691 has 2 divisors, whose sum is σ = 18880692. Its totient is φ = 18880690.

The previous prime is 18880679. The next prime is 18880717. The reversal of 18880691 is 19608881.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18880691 is a prime.

It is not a weakly prime, because it can be changed into another prime (18880601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9440345 + 9440346.

It is an arithmetic number, because the mean of its divisors is an integer number (9440346).

Almost surely, 2^18880691 is an apocalyptic number.

18880691 is a deficient number, since it is larger than the sum of its proper divisors (1).

18880691 is an equidigital number, since it uses as much as digits as its factorization.

18880691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27648, while the sum is 41.

The square root of 18880691 is about 4345.1917103852. The cubic root of 18880691 is about 266.2804577704.

The spelling of 18880691 in words is "eighteen million, eight hundred eighty thousand, six hundred ninety-one".