81753451 has 4 divisors (see below), whose sum is σ = 88042192. Its totient is φ = 75464712.

The previous prime is 81753439. The next prime is 81753473. The reversal of 81753451 is 15435718.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15435718 = 2 ⋅7717859.

It is a cyclic number.

It is not a de Polignac number, because 81753451 - 2¹⁷ = 81622379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81753491) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3144351 + ... + 3144376.

It is an arithmetic number, because the mean of its divisors is an integer number (22010548).

Almost surely, 2^81753451 is an apocalyptic number.

81753451 is a deficient number, since it is larger than the sum of its proper divisors (6288741).

81753451 is a wasteful number, since it uses less digits than its factorization.

81753451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6288740.

The product of its digits is 16800, while the sum is 34.

The square root of 81753451 is about 9041.7614987346. The cubic root of 81753451 is about 434.0122937473.

The spelling of 81753451 in words is "eighty-one million, seven hundred fifty-three thousand, four hundred fifty-one".