81622742 has 4 divisors (see below), whose sum is σ = 122434116. Its totient is φ = 40811370.

The previous prime is 81622741. The next prime is 81622769. The reversal of 81622742 is 24722618.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 81622699 and 81622708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81622741) by changing a digit.

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 as a sum of consecutive naturals, namely, 20405684 + ... + 20405687.

It is an arithmetic number, because the mean of its divisors is an integer number (30608529).

Almost surely, 2^81622742 is an apocalyptic number.

81622742 is a deficient number, since it is larger than the sum of its proper divisors (40811374).

81622742 is a wasteful number, since it uses less digits than its factorization.

81622742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40811373.

The product of its digits is 10752, while the sum is 32.

The square root of 81622742 is about 9034.5305356726. The cubic root of 81622742 is about 433.7808679486.

The spelling of 81622742 in words is "eighty-one million, six hundred twenty-two thousand, seven hundred forty-two".