1664861472 has 192 divisors, whose sum is σ = 5251478400. Its totient is φ = 511349760.

The previous prime is 1664861461. The next prime is 1664861533. The reversal of 1664861472 is 2741684661.

1664861472 is a `hidden beast` number, since 166 + 486 + 1 + 4 + 7 + 2 = 666.

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, 606022 + ... + 608762.

It is an arithmetic number, because the mean of its divisors is an integer number (27351450).

Almost surely, 2^1664861472 is an apocalyptic number.

1664861472 is a gapful number since it is divisible by the number (12) 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 1664861472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2625739200).

1664861472 is an abundant number, since it is smaller than the sum of its proper divisors (3586616928).

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

1664861472 is a wasteful number, since it uses less digits than its factorization.

1664861472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2816 (or 2802 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 1664861472 is about 40802.7140273781. The cubic root of 1664861472 is about 1185.2028878695.

The spelling of 1664861472 in words is "one billion, six hundred sixty-four million, eight hundred sixty-one thousand, four hundred seventy-two".