2181620633 has 4 divisors (see below), whose sum is σ = 2276473728. Its totient is φ = 2086767540.

The previous prime is 2181620627. The next prime is 2181620663. The reversal of 2181620633 is 3360261812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2181620633 - 2⁸ = 2181620377 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2181620633.

It is not an unprimeable number, because it can be changed into a prime (2181620663) 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, 47426513 + ... + 47426558.

It is an arithmetic number, because the mean of its divisors is an integer number (569118432).

Almost surely, 2^2181620633 is an apocalyptic number.

2181620633 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

2181620633 is a deficient number, since it is larger than the sum of its proper divisors (94853095).

2181620633 is an equidigital number, since it uses as much as digits as its factorization.

2181620633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94853094.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 2181620633 is about 46707.8219680601. The cubic root of 2181620633 is about 1296.9594885087.

The spelling of 2181620633 in words is "two billion, one hundred eighty-one million, six hundred twenty thousand, six hundred thirty-three".