81431452 has 24 divisors (see below), whose sum is σ = 144576432. Its totient is φ = 40128000.

The previous prime is 81431447. The next prime is 81431509. The reversal of 81431452 is 25413418.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 81431452.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 142327 + ... + 142897.

It is an arithmetic number, because the mean of its divisors is an integer number (6024018).

Almost surely, 2^81431452 is an apocalyptic number.

It is an amenable number.

81431452 is a deficient number, since it is larger than the sum of its proper divisors (63144980).

81431452 is a wasteful number, since it uses less digits than its factorization.

81431452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1029 (or 1027 counting only the distinct ones).

The product of its digits is 3840, while the sum is 28.

The square root of 81431452 is about 9023.9377214163. The cubic root of 81431452 is about 433.4417351418.

The spelling of 81431452 in words is "eighty-one million, four hundred thirty-one thousand, four hundred fifty-two".