1249105381 has 4 divisors (see below), whose sum is σ = 1249178112. Its totient is φ = 1249032652.

The previous prime is 1249105339. The next prime is 1249105399. The reversal of 1249105381 is 1835019421.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1249105381 - 2¹³ = 1249097189 is a prime.

It is a super-2 number, since 2×1249105381² = 3120528505686310322, 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 (1249105301) 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, 5340 + ... + 50266.

It is an arithmetic number, because the mean of its divisors is an integer number (312294528).

Almost surely, 2^1249105381 is an apocalyptic number.

It is an amenable number.

1249105381 is a deficient number, since it is larger than the sum of its proper divisors (72731).

1249105381 is an equidigital number, since it uses as much as digits as its factorization.

1249105381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72730.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 1249105381 is about 35342.6849715751. The cubic root of 1249105381 is about 1076.9602972558.

The spelling of 1249105381 in words is "one billion, two hundred forty-nine million, one hundred five thousand, three hundred eighty-one".