78233712539 has 4 divisors (see below), whose sum is σ = 78234282840. Its totient is φ = 78233142240.

The previous prime is 78233712533. The next prime is 78233712541. The reversal of 78233712539 is 93521733287.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 93521733287 = 1453 ⋅64364579.

It is a cyclic number.

It is not a de Polignac number, because 78233712539 - 2⁸ = 78233712283 is a prime.

It is a super-2 number, since 2×78233712539² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78233712533) 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, 59372 + ... + 399990.

It is an arithmetic number, because the mean of its divisors is an integer number (19558570710).

Almost surely, 2^78233712539 is an apocalyptic number.

78233712539 is a deficient number, since it is larger than the sum of its proper divisors (570301).

78233712539 is a wasteful number, since it uses less digits than its factorization.

78233712539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570300.

The product of its digits is 1905120, while the sum is 50.

The spelling of 78233712539 in words is "seventy-eight billion, two hundred thirty-three million, seven hundred twelve thousand, five hundred thirty-nine".