81267601 has 4 divisors (see below), whose sum is σ = 81852400. Its totient is φ = 80682804.

The previous prime is 81267587. The next prime is 81267623. The reversal of 81267601 is 10676218.

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 a cyclic number.

It is not a de Polignac number, because 81267601 - 2⁵ = 81267569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81267661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 292191 + ... + 292468.

It is an arithmetic number, because the mean of its divisors is an integer number (20463100).

Almost surely, 2^81267601 is an apocalyptic number.

It is an amenable number.

81267601 is a deficient number, since it is larger than the sum of its proper divisors (584799).

81267601 is a wasteful number, since it uses less digits than its factorization.

81267601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 584798.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 81267601 is about 9014.8544636062. The cubic root of 81267601 is about 433.1508256421.

The spelling of 81267601 in words is "eighty-one million, two hundred sixty-seven thousand, six hundred one".