2006156591 has 4 divisors (see below), whose sum is σ = 2111743800. Its totient is φ = 1900569384.

The previous prime is 2006156569. The next prime is 2006156597. The reversal of 2006156591 is 1956516002.

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 2006156591 - 2¹⁴ = 2006140207 is a prime.

It is a super-2 number, since 2×2006156591² = 8049328535225482562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2006156597) 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, 52793576 + ... + 52793613.

It is an arithmetic number, because the mean of its divisors is an integer number (527935950).

Almost surely, 2^2006156591 is an apocalyptic number.

2006156591 is a deficient number, since it is larger than the sum of its proper divisors (105587209).

2006156591 is a wasteful number, since it uses less digits than its factorization.

2006156591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105587208.

The product of its (nonzero) digits is 16200, while the sum is 35.

The square root of 2006156591 is about 44790.1394393900. The cubic root of 2006156591 is about 1261.2125287149.

The spelling of 2006156591 in words is "two billion, six million, one hundred fifty-six thousand, five hundred ninety-one".