81346731 has 4 divisors (see below), whose sum is σ = 108462312. Its totient is φ = 54231152.

The previous prime is 81346721. The next prime is 81346739. The reversal of 81346731 is 13764318.

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

It is a cyclic number.

It is not a de Polignac number, because 81346731 - 2¹³ = 81338539 is a prime.

It is a super-2 number, since 2×81346731² = 13234581288772722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81346692 and 81346701.

It is not an unprimeable number, because it can be changed into a prime (81346739) 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, 13557786 + ... + 13557791.

It is an arithmetic number, because the mean of its divisors is an integer number (27115578).

Almost surely, 2^81346731 is an apocalyptic number.

81346731 is a deficient number, since it is larger than the sum of its proper divisors (27115581).

81346731 is a wasteful number, since it uses less digits than its factorization.

81346731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27115580.

The product of its digits is 12096, while the sum is 33.

The square root of 81346731 is about 9019.2422630729. The cubic root of 81346731 is about 433.2913658896.

The spelling of 81346731 in words is "eighty-one million, three hundred forty-six thousand, seven hundred thirty-one".