1664374740 has 96 divisors (see below), whose sum is σ = 5373285120. Its totient is φ = 377051136.

The previous prime is 1664374739. The next prime is 1664374759. The reversal of 1664374740 is 474734661.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1664374692 and 1664374701.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 29926 + ... + 64994.

It is an arithmetic number, because the mean of its divisors is an integer number (55971720).

Almost surely, 2^1664374740 is an apocalyptic number.

1664374740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1664374740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2686642560).

1664374740 is an abundant number, since it is smaller than the sum of its proper divisors (3708910380).

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

1664374740 is a wasteful number, since it uses less digits than its factorization.

1664374740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35201 (or 35199 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 42.

The square root of 1664374740 is about 40796.7491351946. The cubic root of 1664374740 is about 1185.0873762771.

The spelling of 1664374740 in words is "one billion, six hundred sixty-four million, three hundred seventy-four thousand, seven hundred forty".