78135797 has 4 divisors (see below), whose sum is σ = 78155616. Its totient is φ = 78115980.

The previous prime is 78135781. The next prime is 78135803. The reversal of 78135797 is 79753187.

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: 79753187 = 8419 ⋅9473.

It is a cyclic number.

It is not a de Polignac number, because 78135797 - 2⁴ = 78135781 is a prime.

It is a super-2 number, since 2×78135797² = 12210405545650418, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78135767) 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, 1763 + ... + 12624.

It is an arithmetic number, because the mean of its divisors is an integer number (19538904).

Almost surely, 2^78135797 is an apocalyptic number.

It is an amenable number.

78135797 is a deficient number, since it is larger than the sum of its proper divisors (19819).

78135797 is a wasteful number, since it uses less digits than its factorization.

78135797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19818.

The product of its digits is 370440, while the sum is 47.

The square root of 78135797 is about 8839.4455142843. The cubic root of 78135797 is about 427.5136792130.

The spelling of 78135797 in words is "seventy-eight million, one hundred thirty-five thousand, seven hundred ninety-seven".