1372455221 has 4 divisors (see below), whose sum is σ = 1381197132. Its totient is φ = 1363713312.

The previous prime is 1372455187. The next prime is 1372455257. The reversal of 1372455221 is 1225542731.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 365344996 + 1007110225 = 19114^2 + 31735^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1372455221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1372485221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4370720 + ... + 4371033.

It is an arithmetic number, because the mean of its divisors is an integer number (345299283).

Almost surely, 2^1372455221 is an apocalyptic number.

It is an amenable number.

1372455221 is a deficient number, since it is larger than the sum of its proper divisors (8741911).

1372455221 is an equidigital number, since it uses as much as digits as its factorization.

1372455221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8741910.

The product of its digits is 16800, while the sum is 32.

The square root of 1372455221 is about 37046.6627511845. The cubic root of 1372455221 is about 1111.3036170561.

Adding to 1372455221 its reverse (1225542731), we get a palindrome (2597997952).

The spelling of 1372455221 in words is "one billion, three hundred seventy-two million, four hundred fifty-five thousand, two hundred twenty-one".