1251251149 has 4 divisors (see below), whose sum is σ = 1251366336. Its totient is φ = 1251135964.

The previous prime is 1251251101. The next prime is 1251251179. The reversal of 1251251149 is 9411521521.

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: 9411521521 = 17 ⋅553618913.

It is a cyclic number.

It is not a de Polignac number, because 1251251149 - 2⁷ = 1251251021 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1251251149.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1251251179) 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, 39379 + ... + 63664.

It is an arithmetic number, because the mean of its divisors is an integer number (312841584).

Almost surely, 2^1251251149 is an apocalyptic number.

It is an amenable number.

1251251149 is a deficient number, since it is larger than the sum of its proper divisors (115187).

1251251149 is a wasteful number, since it uses less digits than its factorization.

1251251149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115186.

The product of its digits is 3600, while the sum is 31.

The square root of 1251251149 is about 35373.0285528395. The cubic root of 1251251149 is about 1077.5766276794.

The spelling of 1251251149 in words is "one billion, two hundred fifty-one million, two hundred fifty-one thousand, one hundred forty-nine".