6650990181 has 36 divisors (see below), whose sum is σ = 10923925740. Its totient is φ = 3891888000.

The previous prime is 6650990153. The next prime is 6650990191. The reversal of 6650990181 is 1810990566.

6650990181 is a `hidden beast` number, since 66 + 509 + 9 + 0 + 1 + 81 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1039482081 + 5611508100 = 32241^2 + 74910^2 .

It is not a de Polignac number, because 6650990181 - 2²¹ = 6648893029 is a prime.

It is a super-2 number, since 2×6650990181² = 88471340775516825522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6650990131) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 73720 + ... + 136881.

Almost surely, 2^6650990181 is an apocalyptic number.

It is an amenable number.

6650990181 is a deficient number, since it is larger than the sum of its proper divisors (4272935559).

6650990181 is a wasteful number, since it uses less digits than its factorization.

6650990181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210658 (or 210644 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The square root of 6650990181 is about 81553.6031147613. The cubic root of 6650990181 is about 1880.5956861589.

The spelling of 6650990181 in words is "six billion, six hundred fifty million, nine hundred ninety thousand, one hundred eighty-one".