81342838621 has 8 divisors (see below), whose sum is σ = 88761420000. Its totient is φ = 73928220240.

The previous prime is 81342838609. The next prime is 81342838639. The reversal of 81342838621 is 12683824318.

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

It is a cyclic number.

It is not a de Polignac number, because 81342838621 - 2¹¹ = 81342836573 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81342838691) 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, 947746 + ... + 1030003.

It is an arithmetic number, because the mean of its divisors is an integer number (11095177500).

Almost surely, 2^81342838621 is an apocalyptic number.

It is an amenable number.

81342838621 is a deficient number, since it is larger than the sum of its proper divisors (7418581379).

81342838621 is a wasteful number, since it uses less digits than its factorization.

81342838621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1981499.

The product of its digits is 442368, while the sum is 46.

The spelling of 81342838621 in words is "eighty-one billion, three hundred forty-two million, eight hundred thirty-eight thousand, six hundred twenty-one".