81302690742 has 64 divisors (see below), whose sum is σ = 200397195264. Its totient is φ = 21413808000.

The previous prime is 81302690741. The next prime is 81302690747. The reversal of 81302690742 is 24709620318.

It is a super-2 number, since 2×81302690742² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 81302690694 and 81302690703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81302690741) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 310908 + ... + 509184.

It is an arithmetic number, because the mean of its divisors is an integer number (3131206176).

Almost surely, 2^81302690742 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81302690742, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100198597632).

81302690742 is an abundant number, since it is smaller than the sum of its proper divisors (119094504522).

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

81302690742 is a wasteful number, since it uses less digits than its factorization.

81302690742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199053.

The product of its (nonzero) digits is 145152, while the sum is 42.

The spelling of 81302690742 in words is "eighty-one billion, three hundred two million, six hundred ninety thousand, seven hundred forty-two".