2640291851 has 4 divisors (see below), whose sum is σ = 2779254600. Its totient is φ = 2501329104.

The previous prime is 2640291833. The next prime is 2640291859. The reversal of 2640291851 is 1581920462.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2640291851 - 2¹⁰ = 2640290827 is a prime.

It is a super-2 number, since 2×2640291851² = 13942282116914012402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2640291859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69481346 + ... + 69481383.

It is an arithmetic number, because the mean of its divisors is an integer number (694813650).

Almost surely, 2^2640291851 is an apocalyptic number.

2640291851 is a deficient number, since it is larger than the sum of its proper divisors (138962749).

2640291851 is a wasteful number, since it uses less digits than its factorization.

2640291851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138962748.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 2640291851 is about 51383.7703073646. The cubic root of 2640291851 is about 1382.1355737703.

The spelling of 2640291851 in words is "two billion, six hundred forty million, two hundred ninety-one thousand, eight hundred fifty-one".