1690097993 has 4 divisors (see below), whose sum is σ = 1789515540. Its totient is φ = 1590680448.

The previous prime is 1690097963. The next prime is 1690097999. The reversal of 1690097993 is 3997900961.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3997900961 = 223 ⋅17927807.

It can be written as a sum of positive squares in 2 ways, for example, as 560600329 + 1129497664 = 23677^2 + 33608^2 .

It is a cyclic number.

It is not a de Polignac number, because 1690097993 - 2¹⁶ = 1690032457 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1690097999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49708748 + ... + 49708781.

It is an arithmetic number, because the mean of its divisors is an integer number (447378885).

Almost surely, 2^1690097993 is an apocalyptic number.

It is an amenable number.

1690097993 is a deficient number, since it is larger than the sum of its proper divisors (99417547).

1690097993 is an equidigital number, since it uses as much as digits as its factorization.

1690097993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99417546.

The product of its (nonzero) digits is 826686, while the sum is 53.

The square root of 1690097993 is about 41110.8014151999. The cubic root of 1690097993 is about 1191.1614470844.

The spelling of 1690097993 in words is "one billion, six hundred ninety million, ninety-seven thousand, nine hundred ninety-three".