6453131156721 has 12 divisors (see below), whose sum is σ = 9326883537972. Its totient is φ = 4299459396576.

The previous prime is 6453131156617. The next prime is 6453131156729. The reversal of 6453131156721 is 1276511313546.

6453131156721 is a `hidden beast` number, since 6 + 4 + 5 + 31 + 31 + 1 + 567 + 21 = 666.

6453131156721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 3101068170225 + 3352062986496 = 1760985^2 + 1830864^2 .

It is not a de Polignac number, because 6453131156721 - 2¹⁵ = 6453131123953 is a prime.

It is a super-2 number, since 2×6453131156721² (a number of 26 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6453131156729) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 218987886 + ... + 219017351.

It is an arithmetic number, because the mean of its divisors is an integer number (777240294831).

Almost surely, 2^{6453131156721} is an apocalyptic number.

It is an amenable number.

6453131156721 is a deficient number, since it is larger than the sum of its proper divisors (2873752381251).

6453131156721 is a wasteful number, since it uses less digits than its factorization.

6453131156721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438006880 (or 438006877 counting only the distinct ones).

The product of its digits is 453600, while the sum is 45.

The spelling of 6453131156721 in words is "six trillion, four hundred fifty-three billion, one hundred thirty-one million, one hundred fifty-six thousand, seven hundred twenty-one".