78241581 has 24 divisors (see below), whose sum is σ = 124502976. Its totient is φ = 46952640.

The previous prime is 78241577. The next prime is 78241651. The reversal of 78241581 is 18514287.

78241581 is a `hidden beast` number, since 78 + 2 + 4 + 1 + 581 = 666.

It is not a de Polignac number, because 78241581 - 2² = 78241577 is a prime.

It is a super-2 number, since 2×78241581² = 12243489994759122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78248581) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6361 + ... + 14033.

It is an arithmetic number, because the mean of its divisors is an integer number (5187624).

Almost surely, 2^78241581 is an apocalyptic number.

It is an amenable number.

78241581 is a deficient number, since it is larger than the sum of its proper divisors (46261395).

78241581 is a wasteful number, since it uses less digits than its factorization.

78241581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7793 (or 7790 counting only the distinct ones).

The product of its digits is 17920, while the sum is 36.

The square root of 78241581 is about 8845.4271236611. The cubic root of 78241581 is about 427.7065217395.

The spelling of 78241581 in words is "seventy-eight million, two hundred forty-one thousand, five hundred eighty-one".