2151587666 has 16 divisors (see below), whose sum is σ = 3325233624. Its totient is φ = 1043362944.

The previous prime is 2151587663. The next prime is 2151587699. The reversal of 2151587666 is 6667851512.

It can be written as a sum of positive squares in 4 ways, for example, as 833534641 + 1318053025 = 28871^2 + 36305^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 2151587666.

It is not an unprimeable number, because it can be changed into a prime (2151587663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23285 + ... + 69608.

Almost surely, 2^2151587666 is an apocalyptic number.

2151587666 is a deficient number, since it is larger than the sum of its proper divisors (1173645958).

2151587666 is a wasteful number, since it uses less digits than its factorization.

2151587666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93245.

The product of its digits is 604800, while the sum is 47.

The square root of 2151587666 is about 46385.2095608072. The cubic root of 2151587666 is about 1290.9804988731.

The spelling of 2151587666 in words is "two billion, one hundred fifty-one million, five hundred eighty-seven thousand, six hundred sixty-six".