81353595442 has 64 divisors (see below), whose sum is σ = 143256960000. Its totient is φ = 34634658240.

The previous prime is 81353595431. The next prime is 81353595467. The reversal of 81353595442 is 24459535318.

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 89300967 + ... + 89301877.

It is an arithmetic number, because the mean of its divisors is an integer number (2238390000).

Almost surely, 2^81353595442 is an apocalyptic number.

81353595442 is a deficient number, since it is larger than the sum of its proper divisors (61903364558).

81353595442 is a wasteful number, since it uses less digits than its factorization.

81353595442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1656 (or 1642 counting only the distinct ones).

The product of its digits is 2592000, while the sum is 49.

The spelling of 81353595442 in words is "eighty-one billion, three hundred fifty-three million, five hundred ninety-five thousand, four hundred forty-two".