1604664987 has 8 divisors (see below), whose sum is σ = 2139769104. Its totient is φ = 1069668768.

The previous prime is 1604664977. The next prime is 1604664991. The reversal of 1604664987 is 7894664061.

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

It is not a de Polignac number, because 1604664987 - 2⁶ = 1604664923 is a prime.

It is a super-3 number, since 3×1604664987³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1604664907) 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, 18853 + ... + 59705.

It is an arithmetic number, because the mean of its divisors is an integer number (267471138).

Almost surely, 2^1604664987 is an apocalyptic number.

1604664987 is a deficient number, since it is larger than the sum of its proper divisors (535104117).

1604664987 is a wasteful number, since it uses less digits than its factorization.

1604664987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53949.

The product of its (nonzero) digits is 1741824, while the sum is 51.

The square root of 1604664987 is about 40058.2698952414. The cubic root of 1604664987 is about 1170.7427010634.

The spelling of 1604664987 in words is "one billion, six hundred four million, six hundred sixty-four thousand, nine hundred eighty-seven".