81234700428 has 48 divisors (see below), whose sum is σ = 222480629504. Its totient is φ = 22582618560.

The previous prime is 81234700409. The next prime is 81234700433. The reversal of 81234700428 is 82400743218.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13065538 + ... + 13071753.

Almost surely, 2^81234700428 is an apocalyptic number.

It is an amenable number.

81234700428 is an abundant number, since it is smaller than the sum of its proper divisors (141245929076).

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

81234700428 is a wasteful number, since it uses less digits than its factorization.

81234700428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26137342 (or 26137340 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 39.

The spelling of 81234700428 in words is "eighty-one billion, two hundred thirty-four million, seven hundred thousand, four hundred twenty-eight".