2635221643 has 4 divisors (see below), whose sum is σ = 2635483968. Its totient is φ = 2634959320.

The previous prime is 2635221637. The next prime is 2635221661. The reversal of 2635221643 is 3461225362.

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 2635221643 - 2¹⁷ = 2635090571 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2635221599 and 2635221608.

It is not an unprimeable number, because it can be changed into a prime (2635221443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115468 + ... + 136393.

It is an arithmetic number, because the mean of its divisors is an integer number (658870992).

Almost surely, 2^2635221643 is an apocalyptic number.

2635221643 is a deficient number, since it is larger than the sum of its proper divisors (262325).

2635221643 is a wasteful number, since it uses less digits than its factorization.

2635221643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262324.

The product of its digits is 51840, while the sum is 34.

The square root of 2635221643 is about 51334.4099313511. The cubic root of 2635221643 is about 1381.2502921780.

The spelling of 2635221643 in words is "two billion, six hundred thirty-five million, two hundred twenty-one thousand, six hundred forty-three".