1690864641 has 12 divisors (see below), whose sum is σ = 2501930340. Its totient is φ = 1099749120.

The previous prime is 1690864627. The next prime is 1690864649. The reversal of 1690864641 is 1464680961.

It can be written as a sum of positive squares in 2 ways, for example, as 26224641 + 1664640000 = 5121^2 + 40800^2 .

It is not a de Polignac number, because 1690864641 - 2²¹ = 1688767489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1690864649) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2290776 + ... + 2291513.

It is an arithmetic number, because the mean of its divisors is an integer number (208494195).

Almost surely, 2^1690864641 is an apocalyptic number.

It is an amenable number.

1690864641 is a deficient number, since it is larger than the sum of its proper divisors (811065699).

1690864641 is a wasteful number, since it uses less digits than its factorization.

1690864641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4582336 (or 4582333 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The square root of 1690864641 is about 41120.1245255897. The cubic root of 1690864641 is about 1191.3415280619.

The spelling of 1690864641 in words is "one billion, six hundred ninety million, eight hundred sixty-four thousand, six hundred forty-one".