81042451 has 16 divisors (see below), whose sum is σ = 98594496. Its totient is φ = 65028096.

The previous prime is 81042449. The next prime is 81042457. The reversal of 81042451 is 15424018.

It is not a de Polignac number, because 81042451 - 2¹ = 81042449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81042457) 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, 21715 + ... + 25171.

It is an arithmetic number, because the mean of its divisors is an integer number (6162156).

Almost surely, 2^81042451 is an apocalyptic number.

81042451 is a deficient number, since it is larger than the sum of its proper divisors (17552045).

81042451 is a wasteful number, since it uses less digits than its factorization.

81042451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3678.

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 81042451 is about 9002.3580799699. The cubic root of 81042451 is about 432.7504442328.

Adding to 81042451 its reverse (15424018), we get a palindrome (96466469).

The spelling of 81042451 in words is "eighty-one million, forty-two thousand, four hundred fifty-one".