81574431 has 8 divisors (see below), whose sum is σ = 108842160. Its totient is φ = 54344832.

The previous prime is 81574421. The next prime is 81574439. The reversal of 81574431 is 13447518.

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

It is not a de Polignac number, because 81574431 - 2¹⁰ = 81573407 is a prime.

It is a super-2 number, since 2×81574431² = 13308775585947522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81574392 and 81574401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81574439) 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, 4096 + ... + 13413.

It is an arithmetic number, because the mean of its divisors is an integer number (13605270).

Almost surely, 2^81574431 is an apocalyptic number.

81574431 is a deficient number, since it is larger than the sum of its proper divisors (27267729).

81574431 is a wasteful number, since it uses less digits than its factorization.

81574431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19065.

The product of its digits is 13440, while the sum is 33.

The square root of 81574431 is about 9031.8564536866. The cubic root of 81574431 is about 433.6952687519.

The spelling of 81574431 in words is "eighty-one million, five hundred seventy-four thousand, four hundred thirty-one".