1664260620 has 72 divisors (see below), whose sum is σ = 5122093872. Its totient is φ = 403455360.

The previous prime is 1664260571. The next prime is 1664260627. The reversal of 1664260620 is 260624661.

It is a super-2 number, since 2×1664260620² = 5539526822565568800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (1664260627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 107359 + ... + 121878.

Almost surely, 2^1664260620 is an apocalyptic number.

1664260620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1664260620 is an abundant number, since it is smaller than the sum of its proper divisors (3457833252).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1664260620 is a wasteful number, since it uses less digits than its factorization.

1664260620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229271 (or 229258 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 1664260620 is about 40795.3504703661. The cubic root of 1664260620 is about 1185.0602899767.

The spelling of 1664260620 in words is "one billion, six hundred sixty-four million, two hundred sixty thousand, six hundred twenty".