1307221621 has 4 divisors (see below), whose sum is σ = 1317200544. Its totient is φ = 1297242700.

The previous prime is 1307221607. The next prime is 1307221637. The reversal of 1307221621 is 1261227031.

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: 1261227031 = 71 ⋅17763761.

It is a cyclic number.

It is not a de Polignac number, because 1307221621 - 2⁵ = 1307221589 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 (1307222621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4989265 + ... + 4989526.

It is an arithmetic number, because the mean of its divisors is an integer number (329300136).

Almost surely, 2^1307221621 is an apocalyptic number.

It is an amenable number.

1307221621 is a deficient number, since it is larger than the sum of its proper divisors (9978923).

1307221621 is an equidigital number, since it uses as much as digits as its factorization.

1307221621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9978922.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 1307221621 is about 36155.5199243490. The cubic root of 1307221621 is about 1093.4100820995.

Adding to 1307221621 its reverse (1261227031), we get a palindrome (2568448652).

The spelling of 1307221621 in words is "one billion, three hundred seven million, two hundred twenty-one thousand, six hundred twenty-one".