2809641638 has 16 divisors (see below), whose sum is σ = 4241160000. Its totient is φ = 1395933672.

The previous prime is 2809641617. The next prime is 2809641643. The reversal of 2809641638 is 8361469082.

It is a super-2 number, since 2×2809641638² = 15788172267966646088, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2809641592 and 2809641601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 749573 + ... + 753311.

It is an arithmetic number, because the mean of its divisors is an integer number (265072500).

Almost surely, 2^2809641638 is an apocalyptic number.

2809641638 is a deficient number, since it is larger than the sum of its proper divisors (1431518362).

2809641638 is a wasteful number, since it uses less digits than its factorization.

2809641638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6019.

The product of its (nonzero) digits is 497664, while the sum is 47.

The square root of 2809641638 is about 53006.0528430480. The cubic root of 2809641638 is about 1411.0756907228.

The spelling of 2809641638 in words is "two billion, eight hundred nine million, six hundred forty-one thousand, six hundred thirty-eight".