1690408249 has 2 divisors, whose sum is σ = 1690408250. Its totient is φ = 1690408248.

The previous prime is 1690408241. The next prime is 1690408261. The reversal of 1690408249 is 9428040961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1670765625 + 19642624 = 40875^2 + 4432^2 .

It is a cyclic number.

It is not a de Polignac number, because 1690408249 - 2³ = 1690408241 is a prime.

It is not a weakly prime, because it can be changed into another prime (1690408241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 845204124 + 845204125.

It is an arithmetic number, because the mean of its divisors is an integer number (845204125).

Almost surely, 2^1690408249 is an apocalyptic number.

It is an amenable number.

1690408249 is a deficient number, since it is larger than the sum of its proper divisors (1).

1690408249 is an equidigital number, since it uses as much as digits as its factorization.

1690408249 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 124416, while the sum is 43.

The square root of 1690408249 is about 41114.5746542513. The cubic root of 1690408249 is about 1191.2343309005.

The spelling of 1690408249 in words is "one billion, six hundred ninety million, four hundred eight thousand, two hundred forty-nine".