2157194986 has 8 divisors (see below), whose sum is σ = 3347371620. Its totient is φ = 1041404448.

The previous prime is 2157194971. The next prime is 2157194987. The reversal of 2157194986 is 6894917512.

It can be written as a sum of positive squares in 2 ways, for example, as 2155837761 + 1357225 = 46431^2 + 1165^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (2157194987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18596451 + ... + 18596566.

Almost surely, 2^2157194986 is an apocalyptic number.

2157194986 is a deficient number, since it is larger than the sum of its proper divisors (1190176634).

2157194986 is a wasteful number, since it uses less digits than its factorization.

2157194986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37193048.

The product of its digits is 1088640, while the sum is 52.

The square root of 2157194986 is about 46445.6132051241. The cubic root of 2157194986 is about 1292.1010142691.

The spelling of 2157194986 in words is "two billion, one hundred fifty-seven million, one hundred ninety-four thousand, nine hundred eighty-six".