81145477 has 16 divisors (see below), whose sum is σ = 95847552. Its totient is φ = 67245120.

The previous prime is 81145459. The next prime is 81145481. The reversal of 81145477 is 77454118.

It is a cyclic number.

It is not a de Polignac number, because 81145477 - 2⁷ = 81145349 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81145417) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 43902 + ... + 45712.

It is an arithmetic number, because the mean of its divisors is an integer number (5990472).

Almost surely, 2^81145477 is an apocalyptic number.

It is an amenable number.

81145477 is a deficient number, since it is larger than the sum of its proper divisors (14702075).

81145477 is a wasteful number, since it uses less digits than its factorization.

81145477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2028.

The product of its digits is 31360, while the sum is 37.

The square root of 81145477 is about 9008.0784299428. The cubic root of 81145477 is about 432.9337459766.

The spelling of 81145477 in words is "eighty-one million, one hundred forty-five thousand, four hundred seventy-seven".