78587137728331 has 4 divisors (see below), whose sum is σ = 78591172616512. Its totient is φ = 78583102840152.

The previous prime is 78587137728317. The next prime is 78587137728353. The reversal of 78587137728331 is 13382773178587.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78587137728331 - 2¹¹ = 78587137726283 is a prime.

It is a super-2 number, since 2×78587137728331² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78587137728731) 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, 2017414875 + ... + 2017453828.

It is an arithmetic number, because the mean of its divisors is an integer number (19647793154128).

Almost surely, 2^{78587137728331} is an apocalyptic number.

78587137728331 is a deficient number, since it is larger than the sum of its proper divisors (4034888181).

78587137728331 is a wasteful number, since it uses less digits than its factorization.

78587137728331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4034888180.

The product of its digits is 331914240, while the sum is 70.

The spelling of 78587137728331 in words is "seventy-eight trillion, five hundred eighty-seven billion, one hundred thirty-seven million, seven hundred twenty-eight thousand, three hundred thirty-one".