81937887 has 8 divisors (see below), whose sum is σ = 109461504. Its totient is φ = 54519768.

The previous prime is 81937883. The next prime is 81937897. The reversal of 81937887 is 78873918.

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

It is not a de Polignac number, because 81937887 - 2² = 81937883 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81937883) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24543 + ... + 27680.

It is an arithmetic number, because the mean of its divisors is an integer number (13682688).

Almost surely, 2^81937887 is an apocalyptic number.

81937887 is a deficient number, since it is larger than the sum of its proper divisors (27523617).

81937887 is a wasteful number, since it uses less digits than its factorization.

81937887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52749.

The product of its digits is 677376, while the sum is 51.

The square root of 81937887 is about 9051.9548717390. The cubic root of 81937887 is about 434.3384262428.

The spelling of 81937887 in words is "eighty-one million, nine hundred thirty-seven thousand, eight hundred eighty-seven".