2001720791 has 16 divisors (see below), whose sum is σ = 2308965120. Its totient is φ = 1699850880.

The previous prime is 2001720767. The next prime is 2001720793. The reversal of 2001720791 is 1970271002.

It is not a de Polignac number, because 2001720791 - 2⁶ = 2001720727 is a prime.

It is a super-2 number, since 2×2001720791² = 8013772250243331362, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001720793) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 530351 + ... + 534111.

It is an arithmetic number, because the mean of its divisors is an integer number (144310320).

Almost surely, 2^2001720791 is an apocalyptic number.

2001720791 is a deficient number, since it is larger than the sum of its proper divisors (307244329).

2001720791 is a wasteful number, since it uses less digits than its factorization.

2001720791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4454.

The product of its (nonzero) digits is 1764, while the sum is 29.

The square root of 2001720791 is about 44740.5944417371. The cubic root of 2001720791 is about 1260.2822897788.

Adding to 2001720791 its reverse (1970271002), we get a palindrome (3971991793).

The spelling of 2001720791 in words is "two billion, one million, seven hundred twenty thousand, seven hundred ninety-one".