909999949 has 2 divisors, whose sum is σ = 909999950. Its totient is φ = 909999948.

The previous prime is 909999917. The next prime is 909999989. The reversal of 909999949 is 949999909.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 604274724 + 305725225 = 24582^2 + 17485^2 .

It is a cyclic number.

It is not a de Polignac number, because 909999949 - 2⁵ = 909999917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (909999989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 454999974 + 454999975.

It is an arithmetic number, because the mean of its divisors is an integer number (454999975).

Almost surely, 2^909999949 is an apocalyptic number.

It is an amenable number.

909999949 is a deficient number, since it is larger than the sum of its proper divisors (1).

909999949 is an equidigital number, since it uses as much as digits as its factorization.

909999949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19131876, while the sum is 67.

The square root of 909999949 is about 30166.2054126799. The cubic root of 909999949 is about 969.0520902402.

The spelling of 909999949 in words is "nine hundred nine million, nine hundred ninety-nine thousand, nine hundred forty-nine".