81226690 has 8 divisors (see below), whose sum is σ = 146208060. Its totient is φ = 32490672.

The previous prime is 81226667. The next prime is 81226693. The reversal of 81226690 is 9662218.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 73324969 + 7901721 = 8563^2 + 2811^2 .

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

It is a super-2 number, since 2×81226690² = 13195550336712200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81226693) 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, 4061325 + ... + 4061344.

Almost surely, 2^81226690 is an apocalyptic number.

81226690 is a deficient number, since it is larger than the sum of its proper divisors (64981370).

81226690 is a wasteful number, since it uses less digits than its factorization.

81226690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8122676.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 81226690 is about 9012.5850897509. The cubic root of 81226690 is about 433.0781291528.

The spelling of 81226690 in words is "eighty-one million, two hundred twenty-six thousand, six hundred ninety".