1252809381 has 16 divisors (see below), whose sum is σ = 1718086400. Its totient is φ = 811435968.

The previous prime is 1252809359. The next prime is 1252809427. The reversal of 1252809381 is 1839082521.

It is not a de Polignac number, because 1252809381 - 2⁷ = 1252809253 is a prime.

It is a super-2 number, since 2×1252809381² = 3139062690243206322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1252809331) 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, 70740 + ... + 86658.

It is an arithmetic number, because the mean of its divisors is an integer number (107380400).

Almost surely, 2^1252809381 is an apocalyptic number.

It is an amenable number.

1252809381 is a deficient number, since it is larger than the sum of its proper divisors (465277019).

1252809381 is a wasteful number, since it uses less digits than its factorization.

1252809381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16668.

The product of its (nonzero) digits is 34560, while the sum is 39.

The square root of 1252809381 is about 35395.0474077942. The cubic root of 1252809381 is about 1078.0237582293.

The spelling of 1252809381 in words is "one billion, two hundred fifty-two million, eight hundred nine thousand, three hundred eighty-one".