78554681 has 4 divisors (see below), whose sum is σ = 78853632. Its totient is φ = 78255732.

The previous prime is 78554659. The next prime is 78554699. The reversal of 78554681 is 18645587.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18645587 = 73 ⋅255419.

It is a cyclic number.

It is not a de Polignac number, because 78554681 - 2¹⁴ = 78538297 is a prime.

It is a super-2 number, since 2×78554681² = 12341675814023522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78554611) 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, 149081 + ... + 149606.

It is an arithmetic number, because the mean of its divisors is an integer number (19713408).

Almost surely, 2^78554681 is an apocalyptic number.

It is an amenable number.

78554681 is a deficient number, since it is larger than the sum of its proper divisors (298951).

78554681 is a wasteful number, since it uses less digits than its factorization.

78554681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298950.

The product of its digits is 268800, while the sum is 44.

The square root of 78554681 is about 8863.1078634980. The cubic root of 78554681 is about 428.2762813517.

The spelling of 78554681 in words is "seventy-eight million, five hundred fifty-four thousand, six hundred eighty-one".