81527637 has 4 divisors (see below), whose sum is σ = 108703520. Its totient is φ = 54351756.

The previous prime is 81527629. The next prime is 81527647. The reversal of 81527637 is 73672518.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 81527637 - 2³ = 81527629 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81527595 and 81527604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81527647) 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, 13587937 + ... + 13587942.

It is an arithmetic number, because the mean of its divisors is an integer number (27175880).

Almost surely, 2^81527637 is an apocalyptic number.

It is an amenable number.

81527637 is a deficient number, since it is larger than the sum of its proper divisors (27175883).

81527637 is a wasteful number, since it uses less digits than its factorization.

81527637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27175882.

The product of its digits is 70560, while the sum is 39.

The square root of 81527637 is about 9029.2655847527. The cubic root of 81527637 is about 433.6123252041.

The spelling of 81527637 in words is "eighty-one million, five hundred twenty-seven thousand, six hundred thirty-seven".