1145121251 has 4 divisors (see below), whose sum is σ = 1176070512. Its totient is φ = 1114171992.

The previous prime is 1145121247. The next prime is 1145121269. The reversal of 1145121251 is 1521215411.

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 1145121251 - 2² = 1145121247 is a prime.

It is a super-2 number, since 2×1145121251² = 2622605358983610002, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1145121151) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15474575 + ... + 15474648.

It is an arithmetic number, because the mean of its divisors is an integer number (294017628).

Almost surely, 2^1145121251 is an apocalyptic number.

1145121251 is a deficient number, since it is larger than the sum of its proper divisors (30949261).

1145121251 is an equidigital number, since it uses as much as digits as its factorization.

1145121251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30949260.

The product of its digits is 400, while the sum is 23.

The square root of 1145121251 is about 33839.6402315391. The cubic root of 1145121251 is about 1046.2058837081.

Adding to 1145121251 its reverse (1521215411), we get a palindrome (2666336662).

The spelling of 1145121251 in words is "one billion, one hundred forty-five million, one hundred twenty-one thousand, two hundred fifty-one".