1251435648 has 128 divisors (see below), whose sum is σ = 3409182720. Its totient is φ = 406619136.

The previous prime is 1251435641. The next prime is 1251435659. The reversal of 1251435648 is 8465341521.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (1251435641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3267265 + ... + 3267647.

It is an arithmetic number, because the mean of its divisors is an integer number (26634240).

Almost surely, 2^1251435648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1251435648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1704591360).

1251435648 is an abundant number, since it is smaller than the sum of its proper divisors (2157747072).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1251435648 is a wasteful number, since it uses less digits than its factorization.

1251435648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 594 (or 582 counting only the distinct ones).

The product of its digits is 115200, while the sum is 39.

The square root of 1251435648 is about 35375.6363617674. The cubic root of 1251435648 is about 1077.6295885470.

The spelling of 1251435648 in words is "one billion, two hundred fifty-one million, four hundred thirty-five thousand, six hundred forty-eight".