81310535 has 8 divisors (see below), whose sum is σ = 98748720. Its totient is φ = 64264384.

The previous prime is 81310531. The next prime is 81310547. The reversal of 81310535 is 53501318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81310535 - 2² = 81310531 is a prime.

It is a super-2 number, since 2×81310535² = 13222806203972450, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81310531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97550 + ... + 98379.

It is an arithmetic number, because the mean of its divisors is an integer number (12343590).

Almost surely, 2^81310535 is an apocalyptic number.

81310535 is a deficient number, since it is larger than the sum of its proper divisors (17438185).

81310535 is a wasteful number, since it uses less digits than its factorization.

81310535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196017.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 81310535 is about 9017.2354410873. The cubic root of 81310535 is about 433.2270906536.

The spelling of 81310535 in words is "eighty-one million, three hundred ten thousand, five hundred thirty-five".