649041391 has 2 divisors, whose sum is σ = 649041392. Its totient is φ = 649041390.

The previous prime is 649041353. The next prime is 649041397. The reversal of 649041391 is 193140946.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 649041391 - 2²³ = 640652783 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 649041391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (649041397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324520695 + 324520696.

It is an arithmetic number, because the mean of its divisors is an integer number (324520696).

Almost surely, 2^649041391 is an apocalyptic number.

649041391 is a deficient number, since it is larger than the sum of its proper divisors (1).

649041391 is an equidigital number, since it uses as much as digits as its factorization.

649041391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 649041391 is about 25476.2907621969. The cubic root of 649041391 is about 865.8130575718.

The spelling of 649041391 in words is "six hundred forty-nine million, forty-one thousand, three hundred ninety-one".