78825511 has 4 divisors (see below), whose sum is σ = 78863224. Its totient is φ = 78787800.

The previous prime is 78825491. The next prime is 78825517. The reversal of 78825511 is 11552887.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11552887 = 53 ⋅217979.

It is a cyclic number.

It is not a de Polignac number, because 78825511 - 2¹⁷ = 78694439 is a prime.

It is a super-2 number, since 2×78825511² = 12426922368822242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78825517) 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, 15525 + ... + 19966.

It is an arithmetic number, because the mean of its divisors is an integer number (19715806).

Almost surely, 2^78825511 is an apocalyptic number.

78825511 is a deficient number, since it is larger than the sum of its proper divisors (37713).

78825511 is a wasteful number, since it uses less digits than its factorization.

78825511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37712.

The product of its digits is 22400, while the sum is 37.

The square root of 78825511 is about 8878.3732181070. The cubic root of 78825511 is about 428.7679007789.

The spelling of 78825511 in words is "seventy-eight million, eight hundred twenty-five thousand, five hundred eleven".