6525606721 has 4 divisors (see below), whose sum is σ = 6526007344. Its totient is φ = 6525206100.

The previous prime is 6525606697. The next prime is 6525606727. The reversal of 6525606721 is 1276065256.

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-6525606721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6525606727) 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, 174795 + ... + 208816.

It is an arithmetic number, because the mean of its divisors is an integer number (1631501836).

Almost surely, 2^6525606721 is an apocalyptic number.

It is an amenable number.

6525606721 is a deficient number, since it is larger than the sum of its proper divisors (400623).

6525606721 is a wasteful number, since it uses less digits than its factorization.

6525606721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400622.

The product of its (nonzero) digits is 151200, while the sum is 40.

The square root of 6525606721 is about 80781.2275284301. The cubic root of 6525606721 is about 1868.7030690988.

The spelling of 6525606721 in words is "six billion, five hundred twenty-five million, six hundred six thousand, seven hundred twenty-one".