81018456 has 32 divisors (see below), whose sum is σ = 208022640. Its totient is φ = 26275968.

The previous prime is 81018449. The next prime is 81018467. The reversal of 81018456 is 65481018.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44731 + ... + 46506.

Almost surely, 2^81018456 is an apocalyptic number.

It is an amenable number.

81018456 is an abundant number, since it is smaller than the sum of its proper divisors (127004184).

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

81018456 is a wasteful number, since it uses less digits than its factorization.

81018456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91283 (or 91279 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 33.

The square root of 81018456 is about 9001.0252749340. The cubic root of 81018456 is about 432.7077305202.

The spelling of 81018456 in words is "eighty-one million, eighteen thousand, four hundred fifty-six".