3132640721 has 4 divisors (see below), whose sum is σ = 3580160832. Its totient is φ = 2685120612.

The previous prime is 3132640703. The next prime is 3132640723. The reversal of 3132640721 is 1270462313.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1270462313 = 14107 ⋅90059.

It is a cyclic number.

It is not a de Polignac number, because 3132640721 - 2⁶ = 3132640657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3132640723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 223760045 + ... + 223760058.

It is an arithmetic number, because the mean of its divisors is an integer number (895040208).

Almost surely, 2^3132640721 is an apocalyptic number.

It is an amenable number.

3132640721 is a deficient number, since it is larger than the sum of its proper divisors (447520111).

3132640721 is an equidigital number, since it uses as much as digits as its factorization.

3132640721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 447520110.

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 3132640721 is about 55969.9984009290. The cubic root of 3132640721 is about 1463.1994514955.

The spelling of 3132640721 in words is "three billion, one hundred thirty-two million, six hundred forty thousand, seven hundred twenty-one".