1690097991 has 8 divisors (see below), whose sum is σ = 2253813120. Its totient is φ = 1126557432.

The previous prime is 1690097963. The next prime is 1690097999. The reversal of 1690097991 is 1997900961.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1690097991 - 2¹⁷ = 1689966919 is a prime.

It is a congruent number.

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

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19075 + ... + 61188.

It is an arithmetic number, because the mean of its divisors is an integer number (281726640).

Almost surely, 2^1690097991 is an apocalyptic number.

1690097991 is a deficient number, since it is larger than the sum of its proper divisors (563715129).

1690097991 is an equidigital number, since it uses as much as digits as its factorization.

1690097991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87285.

The product of its (nonzero) digits is 275562, while the sum is 51.

The square root of 1690097991 is about 41110.8013908754. The cubic root of 1690097991 is about 1191.1614466145.

The spelling of 1690097991 in words is "one billion, six hundred ninety million, ninety-seven thousand, nine hundred ninety-one".