81474245 has 4 divisors (see below), whose sum is σ = 97769100. Its totient is φ = 65179392.

The previous prime is 81474241. The next prime is 81474269. The reversal of 81474245 is 54247418.

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

It can be written as a sum of positive squares in 2 ways, for example, as 55606849 + 25867396 = 7457^2 + 5086^2 .

It is a cyclic number.

It is not a de Polignac number, because 81474245 - 2² = 81474241 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81474241) 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, 8147420 + ... + 8147429.

It is an arithmetic number, because the mean of its divisors is an integer number (24442275).

Almost surely, 2^81474245 is an apocalyptic number.

It is an amenable number.

81474245 is a deficient number, since it is larger than the sum of its proper divisors (16294855).

81474245 is a wasteful number, since it uses less digits than its factorization.

81474245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16294854.

The product of its digits is 35840, while the sum is 35.

The square root of 81474245 is about 9026.3084924015. The cubic root of 81474245 is about 433.5176477594.

The spelling of 81474245 in words is "eighty-one million, four hundred seventy-four thousand, two hundred forty-five".