78135252 has 96 divisors (see below), whose sum is σ = 205922304. Its totient is φ = 22896000.

The previous prime is 78135241. The next prime is 78135259. The reversal of 78135252 is 25253187.

It is a super-2 number, since 2×78135252² = 12210235210207008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78135259) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 517377 + ... + 517527.

It is an arithmetic number, because the mean of its divisors is an integer number (2145024).

Almost surely, 2^78135252 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78135252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102961152).

78135252 is an abundant number, since it is smaller than the sum of its proper divisors (127787052).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78135252 is a wasteful number, since it uses less digits than its factorization.

78135252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 309 (or 307 counting only the distinct ones).

The product of its digits is 16800, while the sum is 33.

The square root of 78135252 is about 8839.4146865050. The cubic root of 78135252 is about 427.5126852363.

It can be divided in two parts, 78135 and 252, that added together give a palindrome (78387).

The spelling of 78135252 in words is "seventy-eight million, one hundred thirty-five thousand, two hundred fifty-two".