78129726 has 16 divisors (see below), whose sum is σ = 158143104. Its totient is φ = 25729304.

The previous prime is 78129721. The next prime is 78129761. The reversal of 78129726 is 62792187.

It is a super-2 number, since 2×78129726² = 12208508169670152, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78129721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 77946 + ... + 78941.

It is an arithmetic number, because the mean of its divisors is an integer number (9883944).

Almost surely, 2^78129726 is an apocalyptic number.

78129726 is an abundant number, since it is smaller than the sum of its proper divisors (80013378).

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

78129726 is a wasteful number, since it uses less digits than its factorization.

78129726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156975.

The product of its digits is 84672, while the sum is 42.

The square root of 78129726 is about 8839.1021037207. The cubic root of 78129726 is about 427.5026065981.

The spelling of 78129726 in words is "seventy-eight million, one hundred twenty-nine thousand, seven hundred twenty-six".