29391330721 has 3 divisors (see below), whose sum is σ = 29391502161. Its totient is φ = 29391159282.

The previous prime is 29391330649. The next prime is 29391330811. The reversal of 29391330721 is 12703319392.

The square root of 29391330721 is 171439.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 29391330721 - 2⁷ = 29391330593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (29391300721) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 85720 + ... + 257158.

It is an arithmetic number, because the mean of its divisors is an integer number (9797167387).

Almost surely, 2^29391330721 is an apocalyptic number.

29391330721 is the 171439-th square number.

29391330721 is the 85720-th centered octagonal number.

It is an amenable number.

29391330721 is a deficient number, since it is larger than the sum of its proper divisors (171440).

29391330721 is an frugal number, since it uses more digits than its factorization.

29391330721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342878 (or 171439 counting only the distinct ones).

The product of its (nonzero) digits is 61236, while the sum is 40.

The spelling of 29391330721 in words is "twenty-nine billion, three hundred ninety-one million, three hundred thirty thousand, seven hundred twenty-one".