6501721522 has 16 divisors (see below), whose sum is σ = 9859161312. Its totient is φ = 3215496960.

The previous prime is 6501721487. The next prime is 6501721559. The reversal of 6501721522 is 2251271056.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40018 + ... + 120850.

It is an arithmetic number, because the mean of its divisors is an integer number (616197582).

Almost surely, 2^6501721522 is an apocalyptic number.

6501721522 is a deficient number, since it is larger than the sum of its proper divisors (3357439790).

6501721522 is a wasteful number, since it uses less digits than its factorization.

6501721522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81273.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 6501721522 is about 80633.2532023854. The cubic root of 6501721522 is about 1866.4203228415.

Adding to 6501721522 its reverse (2251271056), we get a palindrome (8752992578).

The spelling of 6501721522 in words is "six billion, five hundred one million, seven hundred twenty-one thousand, five hundred twenty-two".