81426553 has 16 divisors (see below), whose sum is σ = 91495936. Its totient is φ = 71953920.

The previous prime is 81426539. The next prime is 81426581. The reversal of 81426553 is 35562418.

It is a cyclic number.

It is not a de Polignac number, because 81426553 - 2²¹ = 79329401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81426593) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38050 + ... + 40132.

It is an arithmetic number, because the mean of its divisors is an integer number (5718496).

Almost surely, 2^81426553 is an apocalyptic number.

It is an amenable number.

81426553 is a deficient number, since it is larger than the sum of its proper divisors (10069383).

81426553 is a wasteful number, since it uses less digits than its factorization.

81426553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2224.

The product of its digits is 28800, while the sum is 34.

The square root of 81426553 is about 9023.6662726411. Note that the first 3 decimals coincide. The cubic root of 81426553 is about 433.4330428671.

The spelling of 81426553 in words is "eighty-one million, four hundred twenty-six thousand, five hundred fifty-three".