81957093 has 8 divisors (see below), whose sum is σ = 109407648. Its totient is φ = 54572304.

The previous prime is 81957091. The next prime is 81957101. The reversal of 81957093 is 39075918.

It is a happy number.

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

It is not a de Polignac number, because 81957093 - 2¹ = 81957091 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81957091) 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, 13455 + ... + 18572.

It is an arithmetic number, because the mean of its divisors is an integer number (13675956).

Almost surely, 2^81957093 is an apocalyptic number.

It is an amenable number.

81957093 is a deficient number, since it is larger than the sum of its proper divisors (27450555).

81957093 is a wasteful number, since it uses less digits than its factorization.

81957093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32883.

The product of its (nonzero) digits is 68040, while the sum is 42.

The square root of 81957093 is about 9053.0156853946. The cubic root of 81957093 is about 434.3723594753.

The spelling of 81957093 in words is "eighty-one million, nine hundred fifty-seven thousand, ninety-three".