78145281 has 12 divisors (see below), whose sum is σ = 113243520. Its totient is φ = 51927480.

The previous prime is 78145279. The next prime is 78145313. The reversal of 78145281 is 18254187.

It is not a de Polignac number, because 78145281 - 2¹ = 78145279 is a prime.

It is a super-2 number, since 2×78145281² = 12213369885137922, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78145231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11161 + ... + 16758.

It is an arithmetic number, because the mean of its divisors is an integer number (9436960).

Almost surely, 2^78145281 is an apocalyptic number.

It is an amenable number.

78145281 is a deficient number, since it is larger than the sum of its proper divisors (35098239).

78145281 is a wasteful number, since it uses less digits than its factorization.

78145281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28236 (or 28233 counting only the distinct ones).

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

The square root of 78145281 is about 8839.9819569952. The cubic root of 78145281 is about 427.5309754923.

The spelling of 78145281 in words is "seventy-eight million, one hundred forty-five thousand, two hundred eighty-one".