1665214920 has 96 divisors (see below), whose sum is σ = 5472862200. Its totient is φ = 439059456.

The previous prime is 1665214919. The next prime is 1665214937. The reversal of 1665214920 is 294125661.

1665214920 is a `hidden beast` number, since 166 + 5 + 2 + 1 + 492 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 882446436 + 782768484 = 29706^2 + 27978^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6054 + ... + 58026.

Almost surely, 2^1665214920 is an apocalyptic number.

1665214920 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 1665214920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2736431100).

1665214920 is an abundant number, since it is smaller than the sum of its proper divisors (3807647280).

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

1665214920 is a wasteful number, since it uses less digits than its factorization.

1665214920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52079 (or 52072 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 1665214920 is about 40807.0449800031. The cubic root of 1665214920 is about 1185.2867542964.

The spelling of 1665214920 in words is "one billion, six hundred sixty-five million, two hundred fourteen thousand, nine hundred twenty".