1249779421 has 4 divisors (see below), whose sum is σ = 1363395744. Its totient is φ = 1136163100.

The previous prime is 1249779347. The next prime is 1249779467.

It is a happy number.

1249779421 is nontrivially palindromic in base 10.

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 1249779421 - 2⁹ = 1249778909 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 (1249779521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56808145 + ... + 56808166.

It is an arithmetic number, because the mean of its divisors is an integer number (340848936).

Almost surely, 2^1249779421 is an apocalyptic number.

1249779421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1249779421 is a deficient number, since it is larger than the sum of its proper divisors (113616323).

1249779421 is a wasteful number, since it uses less digits than its factorization.

1249779421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113616322.

The product of its digits is 254016, while the sum is 46.

The square root of 1249779421 is about 35352.2194635641. The cubic root of 1249779421 is about 1077.1539782152.

The spelling of 1249779421 in words is "one billion, two hundred forty-nine million, seven hundred seventy-nine thousand, four hundred twenty-one".