1171221251 has 6 divisors (see below), whose sum is σ = 1182281100. Its totient is φ = 1160263916.

The previous prime is 1171221197. The next prime is 1171221263. The reversal of 1171221251 is 1521221711.

It is a happy number.

It is not a de Polignac number, because 1171221251 - 2¹⁸ = 1170959107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1171221551) 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, 39701 + ... + 62598.

It is an arithmetic number, because the mean of its divisors is an integer number (197046850).

Almost surely, 2^1171221251 is an apocalyptic number.

1171221251 is a deficient number, since it is larger than the sum of its proper divisors (11059849).

1171221251 is an equidigital number, since it uses as much as digits as its factorization.

1171221251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102513 (or 102406 counting only the distinct ones).

The product of its digits is 280, while the sum is 23.

The square root of 1171221251 is about 34223.1098966765. The cubic root of 1171221251 is about 1054.0947442218.

Adding to 1171221251 its reverse (1521221711), we get a palindrome (2692442962).

The spelling of 1171221251 in words is "one billion, one hundred seventy-one million, two hundred twenty-one thousand, two hundred fifty-one".