81956898 has 24 divisors (see below), whose sum is σ = 188019468. Its totient is φ = 25711872.

The previous prime is 81956893. The next prime is 81956923. The reversal of 81956898 is 89865918.

It can be written as a sum of positive squares in 2 ways, for example, as 79977249 + 1979649 = 8943^2 + 1407^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81956893) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 133611 + ... + 134222.

Almost surely, 2^81956898 is an apocalyptic number.

81956898 is an abundant number, since it is smaller than the sum of its proper divisors (106062570).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81956898 is a wasteful number, since it uses less digits than its factorization.

81956898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267858 (or 267855 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 54.

The square root of 81956898 is about 9053.0049154963. The cubic root of 81956898 is about 434.3720149753.

The spelling of 81956898 in words is "eighty-one million, nine hundred fifty-six thousand, eight hundred ninety-eight".