1250138749 has 4 divisors (see below), whose sum is σ = 1280629980. Its totient is φ = 1219647520.

The previous prime is 1250138731. The next prime is 1250138761. The reversal of 1250138749 is 9478310521.

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

It can be written as a sum of positive squares in 2 ways, for example, as 452923524 + 797215225 = 21282^2 + 28235^2 .

It is a cyclic number.

It is not a de Polignac number, because 1250138749 - 2⁷ = 1250138621 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1250138249) 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, 15245554 + ... + 15245635.

It is an arithmetic number, because the mean of its divisors is an integer number (320157495).

Almost surely, 2^1250138749 is an apocalyptic number.

It is an amenable number.

1250138749 is a deficient number, since it is larger than the sum of its proper divisors (30491231).

1250138749 is an equidigital number, since it uses as much as digits as its factorization.

1250138749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30491230.

The product of its (nonzero) digits is 60480, while the sum is 40.

The square root of 1250138749 is about 35357.3012120552. The cubic root of 1250138749 is about 1077.2572002959.

The spelling of 1250138749 in words is "one billion, two hundred fifty million, one hundred thirty-eight thousand, seven hundred forty-nine".