81377142 has 48 divisors (see below), whose sum is σ = 206546112. Its totient is φ = 21136080.

The previous prime is 81377119. The next prime is 81377167. The reversal of 81377142 is 24177318.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 9348 + ... + 15815.

It is an arithmetic number, because the mean of its divisors is an integer number (4303044).

Almost surely, 2^81377142 is an apocalyptic number.

81377142 is an abundant number, since it is smaller than the sum of its proper divisors (125168970).

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

81377142 is a wasteful number, since it uses less digits than its factorization.

81377142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25193 (or 25186 counting only the distinct ones).

The product of its digits is 9408, while the sum is 33.

The square root of 81377142 is about 9020.9280010429. The cubic root of 81377142 is about 433.3453536442.

The spelling of 81377142 in words is "eighty-one million, three hundred seventy-seven thousand, one hundred forty-two".