1649519257 has 16 divisors (see below), whose sum is σ = 1781136000. Its totient is φ = 1522488960.

The previous prime is 1649519213. The next prime is 1649519281. The reversal of 1649519257 is 7529159461.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1649519257 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1649519257.

It is not an unprimeable number, because it can be changed into a prime (1649519057) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1064119 + ... + 1065667.

It is an arithmetic number, because the mean of its divisors is an integer number (111321000).

Almost surely, 2^1649519257 is an apocalyptic number.

It is an amenable number.

1649519257 is a deficient number, since it is larger than the sum of its proper divisors (131616743).

1649519257 is a wasteful number, since it uses less digits than its factorization.

1649519257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2976.

The product of its digits is 680400, while the sum is 49.

The square root of 1649519257 is about 40614.2740548197. The cubic root of 1649519257 is about 1181.5509761810.

The spelling of 1649519257 in words is "one billion, six hundred forty-nine million, five hundred nineteen thousand, two hundred fifty-seven".