81537214 has 16 divisors (see below), whose sum is σ = 135943920. Its totient is φ = 36362560.

The previous prime is 81537193. The next prime is 81537217. The reversal of 81537214 is 41273518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81537217) 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, 33799 + ... + 36130.

It is an arithmetic number, because the mean of its divisors is an integer number (8496495).

Almost surely, 2^81537214 is an apocalyptic number.

81537214 is a deficient number, since it is larger than the sum of its proper divisors (54406706).

81537214 is a wasteful number, since it uses less digits than its factorization.

81537214 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69995.

The product of its digits is 6720, while the sum is 31.

The square root of 81537214 is about 9029.7959002405. The cubic root of 81537214 is about 433.6293032612.

The spelling of 81537214 in words is "eighty-one million, five hundred thirty-seven thousand, two hundred fourteen".