81424051802 has 8 divisors (see below), whose sum is σ = 129320552916. Its totient is φ = 38317200832.

The previous prime is 81424051777. The next prime is 81424051867. The reversal of 81424051802 is 20815042418.

It is a Cunningham number, because it is equal to 285349²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 81424051801 + 1 = 285349^2 + 1^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1197412493 + ... + 1197412560.

Almost surely, 2^81424051802 is an apocalyptic number.

81424051802 is a deficient number, since it is larger than the sum of its proper divisors (47896501114).

81424051802 is a wasteful number, since it uses less digits than its factorization.

81424051802 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2394825072.

The product of its (nonzero) digits is 20480, while the sum is 35.

The spelling of 81424051802 in words is "eighty-one billion, four hundred twenty-four million, fifty-one thousand, eight hundred two".