1649915309 has 6 divisors (see below), whose sum is σ = 1919289294. Its totient is φ = 1414213080.

The previous prime is 1649915303. The next prime is 1649915329. The reversal of 1649915309 is 9035199461.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 925498084 + 724417225 = 30422^2 + 26915^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1649915309 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1649915303) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 16835822 + ... + 16835919.

It is an arithmetic number, because the mean of its divisors is an integer number (319881549).

Almost surely, 2^1649915309 is an apocalyptic number.

It is an amenable number.

1649915309 is a deficient number, since it is larger than the sum of its proper divisors (269373985).

1649915309 is an equidigital number, since it uses as much as digits as its factorization.

1649915309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33671755 (or 33671748 counting only the distinct ones).

The product of its (nonzero) digits is 262440, while the sum is 47.

The square root of 1649915309 is about 40619.1495356562. The cubic root of 1649915309 is about 1181.6455326561.

The spelling of 1649915309 in words is "one billion, six hundred forty-nine million, nine hundred fifteen thousand, three hundred nine".