1201320251 has 4 divisors (see below), whose sum is σ = 1219250472. Its totient is φ = 1183390032.

The previous prime is 1201320247. The next prime is 1201320259. The reversal of 1201320251 is 1520231021.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1201320251 - 2² = 1201320247 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1201320259) 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, 8965010 + ... + 8965143.

It is an arithmetic number, because the mean of its divisors is an integer number (304812618).

Almost surely, 2^1201320251 is an apocalyptic number.

1201320251 is a deficient number, since it is larger than the sum of its proper divisors (17930221).

1201320251 is an equidigital number, since it uses as much as digits as its factorization.

1201320251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17930220.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 1201320251 is about 34660.0670945686. The cubic root of 1201320251 is about 1063.0481419133.

Adding to 1201320251 its reverse (1520231021), we get a palindrome (2721551272).

The spelling of 1201320251 in words is "one billion, two hundred one million, three hundred twenty thousand, two hundred fifty-one".