402128393 has 4 divisors (see below), whose sum is σ = 402176208. Its totient is φ = 402080580.

The previous prime is 402128383. The next prime is 402128411. The reversal of 402128393 is 393821204.

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

It is a cyclic number.

It is not a de Polignac number, because 402128393 - 2⁶ = 402128329 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (402128383) 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, 7571 + ... + 29352.

It is an arithmetic number, because the mean of its divisors is an integer number (100544052).

Almost surely, 2^402128393 is an apocalyptic number.

It is an amenable number.

402128393 is a deficient number, since it is larger than the sum of its proper divisors (47815).

402128393 is a wasteful number, since it uses less digits than its factorization.

402128393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47814.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 402128393 is about 20053.1392305544. The cubic root of 402128393 is about 738.1108331325.

Adding to 402128393 its reverse (393821204), we get a palindrome (795949597).

The spelling of 402128393 in words is "four hundred two million, one hundred twenty-eight thousand, three hundred ninety-three".