81626045 has 8 divisors (see below), whose sum is σ = 99293496. Its totient is φ = 64406016.

The previous prime is 81626029. The next prime is 81626047. The reversal of 81626045 is 54062618.

It can be written as a sum of positive squares in 4 ways, for example, as 391876 + 81234169 = 626^2 + 9013^2 .

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 81626045 - 2⁴ = 81626029 is a prime.

It is a super-2 number, since 2×81626045² = 13325622444684050, 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 (81626047) 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, 111452 + ... + 112181.

It is an arithmetic number, because the mean of its divisors is an integer number (12411687).

Almost surely, 2^81626045 is an apocalyptic number.

It is an amenable number.

81626045 is a deficient number, since it is larger than the sum of its proper divisors (17667451).

81626045 is a wasteful number, since it uses less digits than its factorization.

81626045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223711.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 81626045 is about 9034.7133324749. The cubic root of 81626045 is about 433.7867190911.

The spelling of 81626045 in words is "eighty-one million, six hundred twenty-six thousand, forty-five".