81377432 has 16 divisors (see below), whose sum is σ = 152681760. Its totient is φ = 40662304.

The previous prime is 81377423. The next prime is 81377441. The reversal of 81377432 is 23477318.

It is an interprime number because it is at equal distance from previous prime (81377423) and next prime (81377441).

It is a junction number, because it is equal to n+sod(n) for n = 81377392 and 81377401.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17498 + ... + 21654.

It is an arithmetic number, because the mean of its divisors is an integer number (9542610).

Almost surely, 2^81377432 is an apocalyptic number.

It is an amenable number.

81377432 is a deficient number, since it is larger than the sum of its proper divisors (71304328).

81377432 is a wasteful number, since it uses less digits than its factorization.

81377432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6610 (or 6606 counting only the distinct ones).

The product of its digits is 28224, while the sum is 35.

The square root of 81377432 is about 9020.9440747629. The cubic root of 81377432 is about 433.3458684079.

The spelling of 81377432 in words is "eighty-one million, three hundred seventy-seven thousand, four hundred thirty-two".