1606664690 has 32 divisors (see below), whose sum is σ = 3014535744. Its totient is φ = 615954240.

The previous prime is 1606664677. The next prime is 1606664707. The reversal of 1606664690 is 964666061.

It is a super-2 number, since 2×1606664690² = 5162742852185592200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7616 + ... + 57195.

It is an arithmetic number, because the mean of its divisors is an integer number (94204242).

Almost surely, 2^1606664690 is an apocalyptic number.

1606664690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1606664690 is a deficient number, since it is larger than the sum of its proper divisors (1407871054).

1606664690 is a wasteful number, since it uses less digits than its factorization.

1606664690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64922.

The product of its (nonzero) digits is 279936, while the sum is 44.

The square root of 1606664690 is about 40083.2220511276. Note that the first 3 decimals coincide. The cubic root of 1606664690 is about 1171.2288182882.

The spelling of 1606664690 in words is "one billion, six hundred six million, six hundred sixty-four thousand, six hundred ninety".