2151979560 has 96 divisors (see below), whose sum is σ = 7045145640. Its totient is φ = 569659392.

The previous prime is 2151979549. The next prime is 2151979589. The reversal of 2151979560 is 659791512.

2151979560 is a `hidden beast` number, since 2 + 1 + 5 + 19 + 79 + 560 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2096357796 + 55621764 = 45786^2 + 7458^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 27504 + ... + 71136.

Almost surely, 2^2151979560 is an apocalyptic number.

2151979560 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 2151979560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3522572820).

2151979560 is an abundant number, since it is smaller than the sum of its proper divisors (4893166080).

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

2151979560 is a wasteful number, since it uses less digits than its factorization.

2151979560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43787 (or 43780 counting only the distinct ones).

The product of its (nonzero) digits is 170100, while the sum is 45.

The square root of 2151979560 is about 46389.4337107061. The cubic root of 2151979560 is about 1291.0588746087.

The spelling of 2151979560 in words is "two billion, one hundred fifty-one million, nine hundred seventy-nine thousand, five hundred sixty".