1251124145261 has 4 divisors (see below), whose sum is σ = 1251130624992. Its totient is φ = 1251117665532.

The previous prime is 1251124145171. The next prime is 1251124145279. The reversal of 1251124145261 is 1625414211521.

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.

It is a cyclic number.

It is not a de Polignac number, because 1251124145261 - 2¹⁸ = 1251123883117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1251129145261) 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, 2941055 + ... + 3339468.

It is an arithmetic number, because the mean of its divisors is an integer number (312782656248).

Almost surely, 2^{1251124145261} is an apocalyptic number.

It is an amenable number.

1251124145261 is a deficient number, since it is larger than the sum of its proper divisors (6479731).

1251124145261 is an equidigital number, since it uses as much as digits as its factorization.

1251124145261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6479730.

The product of its digits is 19200, while the sum is 35.

Adding to 1251124145261 its reverse (1625414211521), we get a palindrome (2876538356782).

The spelling of 1251124145261 in words is "one trillion, two hundred fifty-one billion, one hundred twenty-four million, one hundred forty-five thousand, two hundred sixty-one".