81428052 has 12 divisors (see below), whose sum is σ = 189998816. Its totient is φ = 27142680.

The previous prime is 81428029. The next prime is 81428057. The reversal of 81428052 is 25082418.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81428057) 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, 3392824 + ... + 3392847.

Almost surely, 2^81428052 is an apocalyptic number.

It is an amenable number.

81428052 is an abundant number, since it is smaller than the sum of its proper divisors (108570764).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81428052 is a wasteful number, since it uses less digits than its factorization.

81428052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6785678 (or 6785676 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 30.

The square root of 81428052 is about 9023.7493316249. The cubic root of 81428052 is about 433.4357025734.

The spelling of 81428052 in words is "eighty-one million, four hundred twenty-eight thousand, fifty-two".