1664032620 has 24 divisors (see below), whose sum is σ = 4659291504. Its totient is φ = 443742016.

The previous prime is 1664032583. The next prime is 1664032621. The reversal of 1664032620 is 262304661.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1664032621) 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, 13866879 + ... + 13866998.

It is an arithmetic number, because the mean of its divisors is an integer number (194137146).

Almost surely, 2^1664032620 is an apocalyptic number.

1664032620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1664032620 is an abundant number, since it is smaller than the sum of its proper divisors (2995258884).

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

1664032620 is a wasteful number, since it uses less digits than its factorization.

1664032620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27733889 (or 27733887 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 1664032620 is about 40792.5559385533. Note that the first 3 decimals coincide. The cubic root of 1664032620 is about 1185.0061706314.

The spelling of 1664032620 in words is "one billion, six hundred sixty-four million, thirty-two thousand, six hundred twenty".