1399478749 has 4 divisors (see below), whose sum is σ = 1399616064. Its totient is φ = 1399341436.

The previous prime is 1399478719. The next prime is 1399478767. The reversal of 1399478749 is 9478749931.

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 1399478749 - 2⁹ = 1399478237 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 (1399478719) 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, 52027 + ... + 74200.

It is an arithmetic number, because the mean of its divisors is an integer number (349904016).

Almost surely, 2^1399478749 is an apocalyptic number.

It is an amenable number.

1399478749 is a deficient number, since it is larger than the sum of its proper divisors (137315).

1399478749 is a wasteful number, since it uses less digits than its factorization.

1399478749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137314.

The product of its digits is 13716864, while the sum is 61.

The square root of 1399478749 is about 37409.6077097849. The cubic root of 1399478749 is about 1118.5500872924.

The spelling of 1399478749 in words is "one billion, three hundred ninety-nine million, four hundred seventy-eight thousand, seven hundred forty-nine".