81767401 has 4 divisors (see below), whose sum is σ = 81843712. Its totient is φ = 81691092.

The previous prime is 81767251. The next prime is 81767419. The reversal of 81767401 is 10476718.

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 a de Polignac number, because none of the positive numbers 2^k-81767401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81767471) 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, 36525 + ... + 38698.

It is an arithmetic number, because the mean of its divisors is an integer number (20460928).

Almost surely, 2^81767401 is an apocalyptic number.

It is an amenable number.

81767401 is a deficient number, since it is larger than the sum of its proper divisors (76311).

81767401 is a wasteful number, since it uses less digits than its factorization.

81767401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76310.

The product of its (nonzero) digits is 9408, while the sum is 34.

The square root of 81767401 is about 9042.5328863101. The cubic root of 81767401 is about 434.0369782391.

The spelling of 81767401 in words is "eighty-one million, seven hundred sixty-seven thousand, four hundred one".