81497616 has 20 divisors (see below), whose sum is σ = 210535632. Its totient is φ = 27165856.

The previous prime is 81497597. The next prime is 81497621. The reversal of 81497616 is 61679418.

It is a super-2 number, since 2×81497616² = 13283722827366912, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 848886 + ... + 848981.

Almost surely, 2^81497616 is an apocalyptic number.

It is an amenable number.

81497616 is an abundant number, since it is smaller than the sum of its proper divisors (129038016).

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

81497616 is a wasteful number, since it uses less digits than its factorization.

81497616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1697878 (or 1697872 counting only the distinct ones).

The product of its digits is 72576, while the sum is 42.

The square root of 81497616 is about 9027.6030041202. The cubic root of 81497616 is about 433.5590955091.

The spelling of 81497616 in words is "eighty-one million, four hundred ninety-seven thousand, six hundred sixteen".