2005591283721 has 9 divisors (see below), whose sum is σ = 2896971324429. Its totient is φ = 1337058023436.

The previous prime is 2005591283719. The next prime is 2005591283789. The reversal of 2005591283721 is 1273821955002.

The square root of 2005591283721 is 1416189.

It is a perfect power (a square), and thus also a powerful number.

2005591283721 is a `hidden beast` number, since 2 + 0 + 0 + 5 + 591 + 2 + 8 + 37 + 21 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 2005591283721 - 2¹ = 2005591283719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2005591283021) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4012536 + ... + 4484598.

Almost surely, 2^{2005591283721} is an apocalyptic number.

2005591283721 is the 1416189-th square number.

2005591283721 is the 708095-th centered octagonal number.

It is an amenable number.

2005591283721 is a deficient number, since it is larger than the sum of its proper divisors (891380040708).

2005591283721 is an frugal number, since it uses more digits than its factorization.

2005591283721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 944132 (or 472066 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 45.

The spelling of 2005591283721 in words is "two trillion, five billion, five hundred ninety-one million, two hundred eighty-three thousand, seven hundred twenty-one".