81977262 has 8 divisors (see below), whose sum is σ = 163954536. Its totient is φ = 27325752.

The previous prime is 81977257. The next prime is 81977263. The reversal of 81977262 is 26277918.

It is a sphenic number, since it is the product of 3 distinct primes.

81977262 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81977263) 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 in 3 ways as a sum of consecutive naturals, for example, 6831433 + ... + 6831444.

It is an arithmetic number, because the mean of its divisors is an integer number (20494317).

Almost surely, 2^81977262 is an apocalyptic number.

81977262 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81977262 is a wasteful number, since it uses less digits than its factorization.

81977262 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13662882.

The product of its digits is 84672, while the sum is 42.

The square root of 81977262 is about 9054.1295550704. The cubic root of 81977262 is about 434.4079884337.

The spelling of 81977262 in words is "eighty-one million, nine hundred seventy-seven thousand, two hundred sixty-two".