81825430 has 16 divisors (see below), whose sum is σ = 152037504. Its totient is φ = 31674240.

The previous prime is 81825427. The next prime is 81825433. The reversal of 81825430 is 3452818.

It is an interprime number because it is at equal distance from previous prime (81825427) and next prime (81825433).

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a junction number, because it is equal to n+sod(n) for n = 81825392 and 81825401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81825433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 131667 + ... + 132286.

It is an arithmetic number, because the mean of its divisors is an integer number (9502344).

Almost surely, 2^81825430 is an apocalyptic number.

81825430 is a deficient number, since it is larger than the sum of its proper divisors (70212074).

81825430 is a wasteful number, since it uses less digits than its factorization.

81825430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263991.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 81825430 is about 9045.7409867849. The cubic root of 81825430 is about 434.1396302970.

The spelling of 81825430 in words is "eighty-one million, eight hundred twenty-five thousand, four hundred thirty".