81926087 has 4 divisors (see below), whose sum is σ = 84568896. Its totient is φ = 79283280.

The previous prime is 81926083. The next prime is 81926099. The reversal of 81926087 is 78062918.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81926087 - 2² = 81926083 is a prime.

It is a super-2 number, since 2×81926087² = 13423767462263138, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81926083) 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, 1321358 + ... + 1321419.

It is an arithmetic number, because the mean of its divisors is an integer number (21142224).

Almost surely, 2^81926087 is an apocalyptic number.

81926087 is a deficient number, since it is larger than the sum of its proper divisors (2642809).

81926087 is a wasteful number, since it uses less digits than its factorization.

81926087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2642808.

The product of its (nonzero) digits is 48384, while the sum is 41.

The square root of 81926087 is about 9051.3030553617. The cubic root of 81926087 is about 434.3175753289.

The spelling of 81926087 in words is "eighty-one million, nine hundred twenty-six thousand, eighty-seven".