78139502 has 8 divisors (see below), whose sum is σ = 133953456. Its totient is φ = 33488352.

The previous prime is 78139493. The next prime is 78139507. The reversal of 78139502 is 20593187.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×78139502² = 12211563545616008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78139507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2790683 + ... + 2790710.

It is an arithmetic number, because the mean of its divisors is an integer number (16744182).

Almost surely, 2^78139502 is an apocalyptic number.

78139502 is a deficient number, since it is larger than the sum of its proper divisors (55813954).

78139502 is a wasteful number, since it uses less digits than its factorization.

78139502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5581402.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 78139502 is about 8839.6550837688. The cubic root of 78139502 is about 427.5204363086.

The spelling of 78139502 in words is "seventy-eight million, one hundred thirty-nine thousand, five hundred two".