81027629391 has 8 divisors (see below), whose sum is σ = 108103990960. Its totient is φ = 53984843712.

The previous prime is 81027629381. The next prime is 81027629429. The reversal of 81027629391 is 19392672018.

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

It is not a de Polignac number, because 81027629391 - 2⁶ = 81027629327 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81027629391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81027629321) 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, 8388340 + ... + 8397993.

It is an arithmetic number, because the mean of its divisors is an integer number (13512998870).

Almost surely, 2^81027629391 is an apocalyptic number.

81027629391 is a deficient number, since it is larger than the sum of its proper divisors (27076361569).

81027629391 is a wasteful number, since it uses less digits than its factorization.

81027629391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16787945.

The product of its (nonzero) digits is 326592, while the sum is 48.

The spelling of 81027629391 in words is "eighty-one billion, twenty-seven million, six hundred twenty-nine thousand, three hundred ninety-one".