81409290240 has 104 divisors (see below), whose sum is σ = 260478124848. Its totient is φ = 21709127680.

The previous prime is 81409290223. The next prime is 81409290271. The reversal of 81409290240 is 4209290418.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 601071 + ... + 723950.

Almost surely, 2^81409290240 is an apocalyptic number.

81409290240 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81409290240 is an abundant number, since it is smaller than the sum of its proper divisors (179068834608).

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

81409290240 is a wasteful number, since it uses less digits than its factorization.

81409290240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1325053 (or 1325031 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 39.

The spelling of 81409290240 in words is "eighty-one billion, four hundred nine million, two hundred ninety thousand, two hundred forty".