1321201251 has 6 divisors (see below), whose sum is σ = 1908401820. Its totient is φ = 880800828.

The previous prime is 1321201243. The next prime is 1321201253. The reversal of 1321201251 is 1521021231.

It is not a de Polignac number, because 1321201251 - 2³ = 1321201243 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1321201253) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 73400061 + ... + 73400078.

It is an arithmetic number, because the mean of its divisors is an integer number (318066970).

Almost surely, 2^1321201251 is an apocalyptic number.

1321201251 is a deficient number, since it is larger than the sum of its proper divisors (587200569).

1321201251 is a wasteful number, since it uses less digits than its factorization.

1321201251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146800145 (or 146800142 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 1321201251 is about 36348.3321625628. The cubic root of 1321201251 is about 1097.2939686547.

Adding to 1321201251 its reverse (1521021231), we get a palindrome (2842222482).

The spelling of 1321201251 in words is "one billion, three hundred twenty-one million, two hundred one thousand, two hundred fifty-one".