81275742 has 24 divisors (see below), whose sum is σ = 186456816. Its totient is φ = 25498176.

The previous prime is 81275713. The next prime is 81275743. The reversal of 81275742 is 24757218.

81275742 is a `hidden beast` number, since 81 + 2 + 7 + 574 + 2 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 81275697 and 81275706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81275743) 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, 132498 + ... + 133109.

It is an arithmetic number, because the mean of its divisors is an integer number (7769034).

Almost surely, 2^81275742 is an apocalyptic number.

81275742 is an abundant number, since it is smaller than the sum of its proper divisors (105181074).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81275742 is a wasteful number, since it uses less digits than its factorization.

81275742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265632 (or 265629 counting only the distinct ones).

The product of its digits is 31360, while the sum is 36.

The square root of 81275742 is about 9015.3059848238. The cubic root of 81275742 is about 433.1652888192.

The spelling of 81275742 in words is "eighty-one million, two hundred seventy-five thousand, seven hundred forty-two".