2171720429 has 4 divisors (see below), whose sum is σ = 2172120576. Its totient is φ = 2171320284.

The previous prime is 2171720371. The next prime is 2171720449. The reversal of 2171720429 is 9240271712.

2171720429 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 a de Polignac number, because none of the positive numbers 2^k-2171720429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2171720449) 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, 191819 + ... + 202824.

It is an arithmetic number, because the mean of its divisors is an integer number (543030144).

Almost surely, 2^2171720429 is an apocalyptic number.

It is an amenable number.

2171720429 is a deficient number, since it is larger than the sum of its proper divisors (400147).

2171720429 is an equidigital number, since it uses as much as digits as its factorization.

2171720429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400146.

The product of its (nonzero) digits is 14112, while the sum is 35.

The square root of 2171720429 is about 46601.7213094109. The cubic root of 2171720429 is about 1294.9946440648.

The spelling of 2171720429 in words is "two billion, one hundred seventy-one million, seven hundred twenty thousand, four hundred twenty-nine".