2638687152861 has 12 divisors (see below), whose sum is σ = 3811540333692. Its totient is φ = 1759077075456.

The previous prime is 2638687152851. The next prime is 2638687152869. The reversal of 2638687152861 is 1682517868362.

2638687152861 is a `hidden beast` number, since 2 + 6 + 38 + 6 + 8 + 71 + 528 + 6 + 1 = 666.

2638687152861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 2556944912025 + 81742240836 = 1599045^2 + 285906^2 .

It is not a de Polignac number, because 2638687152861 - 2¹⁵ = 2638687120093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2638687152869) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3622386 + ... + 4289411.

It is an arithmetic number, because the mean of its divisors is an integer number (317628361141).

Almost surely, 2^{2638687152861} is an apocalyptic number.

It is an amenable number.

2638687152861 is a deficient number, since it is larger than the sum of its proper divisors (1172853180831).

2638687152861 is a wasteful number, since it uses less digits than its factorization.

2638687152861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7948860 (or 7948857 counting only the distinct ones).

The product of its digits is 46448640, while the sum is 63.

The spelling of 2638687152861 in words is "two trillion, six hundred thirty-eight billion, six hundred eighty-seven million, one hundred fifty-two thousand, eight hundred sixty-one".