81264457 has 8 divisors (see below), whose sum is σ = 83131776. Its totient is φ = 79402992.

The previous prime is 81264439. The next prime is 81264461. The reversal of 81264457 is 75446218.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81264457 - 2¹⁹ = 80740169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81264487) 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, 39078 + ... + 41104.

It is an arithmetic number, because the mean of its divisors is an integer number (10391472).

Almost surely, 2^81264457 is an apocalyptic number.

It is an amenable number.

81264457 is a deficient number, since it is larger than the sum of its proper divisors (1867319).

81264457 is a wasteful number, since it uses less digits than its factorization.

81264457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2927.

The product of its digits is 53760, while the sum is 37.

The square root of 81264457 is about 9014.6800830645. The cubic root of 81264457 is about 433.1452398008.

The spelling of 81264457 in words is "eighty-one million, two hundred sixty-four thousand, four hundred fifty-seven".