81667762142 has 4 divisors (see below), whose sum is σ = 122501643216. Its totient is φ = 40833881070.

The previous prime is 81667762129. The next prime is 81667762159. The reversal of 81667762142 is 24126776618.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20416940534 + ... + 20416940537.

It is an arithmetic number, because the mean of its divisors is an integer number (30625410804).

Almost surely, 2^81667762142 is an apocalyptic number.

81667762142 is a deficient number, since it is larger than the sum of its proper divisors (40833881074).

81667762142 is a wasteful number, since it uses less digits than its factorization.

81667762142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40833881073.

The product of its digits is 1354752, while the sum is 50.

The spelling of 81667762142 in words is "eighty-one billion, six hundred sixty-seven million, seven hundred sixty-two thousand, one hundred forty-two".