391648867 has 2 divisors, whose sum is σ = 391648868. Its totient is φ = 391648866.

The previous prime is 391648841. The next prime is 391648877. The reversal of 391648867 is 768846193.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-391648867 is a prime.

It is not a weakly prime, because it can be changed into another prime (391648877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195824433 + 195824434.

It is an arithmetic number, because the mean of its divisors is an integer number (195824434).

Almost surely, 2^391648867 is an apocalyptic number.

391648867 is a deficient number, since it is larger than the sum of its proper divisors (1).

391648867 is an equidigital number, since it uses as much as digits as its factorization.

391648867 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1741824, while the sum is 52.

The square root of 391648867 is about 19790.1204392495. The cubic root of 391648867 is about 731.6425558086.

The spelling of 391648867 in words is "three hundred ninety-one million, six hundred forty-eight thousand, eight hundred sixty-seven".