393428749 has 4 divisors (see below), whose sum is σ = 449632864. Its totient is φ = 337224636.

The previous prime is 393428729. The next prime is 393428863. The reversal of 393428749 is 947824393.

It is a happy number.

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 an emirpimes, since its reverse is a distinct semiprime: 947824393 = 83 ⋅11419571.

It is not a de Polignac number, because 393428749 - 2⁹ = 393428237 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 (393428729) 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, 28102047 + ... + 28102060.

It is an arithmetic number, because the mean of its divisors is an integer number (112408216).

Almost surely, 2^393428749 is an apocalyptic number.

It is an amenable number.

393428749 is a deficient number, since it is larger than the sum of its proper divisors (56204115).

393428749 is an equidigital number, since it uses as much as digits as its factorization.

393428749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56204114.

The product of its digits is 1306368, while the sum is 49.

The square root of 393428749 is about 19835.0384169025. The cubic root of 393428749 is about 732.7492185880.

The spelling of 393428749 in words is "three hundred ninety-three million, four hundred twenty-eight thousand, seven hundred forty-nine".