1664162491 has 8 divisors (see below), whose sum is σ = 1724192768. Its totient is φ = 1604529000.

The previous prime is 1664162483. The next prime is 1664162509. The reversal of 1664162491 is 1942614661.

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

It is not a de Polignac number, because 1664162491 - 2³ = 1664162483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1664172491) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90645 + ... + 107446.

It is an arithmetic number, because the mean of its divisors is an integer number (215524096).

Almost surely, 2^1664162491 is an apocalyptic number.

1664162491 is a deficient number, since it is larger than the sum of its proper divisors (60030277).

1664162491 is a wasteful number, since it uses less digits than its factorization.

1664162491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198393.

The product of its digits is 62208, while the sum is 40.

The square root of 1664162491 is about 40794.1477543042. The cubic root of 1664162491 is about 1185.0369981386.

The spelling of 1664162491 in words is "one billion, six hundred sixty-four million, one hundred sixty-two thousand, four hundred ninety-one".