135878399 has 4 divisors (see below), whose sum is σ = 143871264. Its totient is φ = 127885536.

The previous prime is 135878359. The next prime is 135878423. The reversal of 135878399 is 993878531.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 993878531 = 17 ⋅58463443.

It is a cyclic number.

It is not a de Polignac number, because 135878399 - 2¹² = 135874303 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 135878399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135878359) 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, 3996407 + ... + 3996440.

It is an arithmetic number, because the mean of its divisors is an integer number (35967816).

Almost surely, 2^135878399 is an apocalyptic number.

135878399 is a deficient number, since it is larger than the sum of its proper divisors (7992865).

135878399 is an equidigital number, since it uses as much as digits as its factorization.

135878399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7992864.

The product of its digits is 1632960, while the sum is 53.

The square root of 135878399 is about 11656.6890239038. The cubic root of 135878399 is about 514.1030026180.

The spelling of 135878399 in words is "one hundred thirty-five million, eight hundred seventy-eight thousand, three hundred ninety-nine".