2665612620 has 144 divisors (see below), whose sum is σ = 8840246688. Its totient is φ = 644782080.

The previous prime is 2665612603. The next prime is 2665612637. The reversal of 2665612620 is 262165662.

2665612620 is a `hidden beast` number, since 26 + 6 + 5 + 6 + 1 + 2 + 620 = 666.

It is an interprime number because it is at equal distance from previous prime (2665612603) and next prime (2665612637).

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 47 ways as a sum of consecutive naturals, for example, 1101652 + ... + 1104068.

It is an arithmetic number, because the mean of its divisors is an integer number (61390602).

Almost surely, 2^2665612620 is an apocalyptic number.

2665612620 is a gapful number since it is divisible by the number (20) 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 2665612620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4420123344).

2665612620 is an abundant number, since it is smaller than the sum of its proper divisors (6174634068).

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

2665612620 is a wasteful number, since it uses less digits than its factorization.

2665612620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3000 (or 2995 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 2665612620 is about 51629.5711777659. The cubic root of 2665612620 is about 1386.5398158380.

The spelling of 2665612620 in words is "two billion, six hundred sixty-five million, six hundred twelve thousand, six hundred twenty".