81006426560 has 56 divisors (see below), whose sum is σ = 198110002560. Its totient is φ = 31526820864.

The previous prime is 81006426559. The next prime is 81006426587. The reversal of 81006426560 is 6562460018.

It is a super-2 number, since 2×81006426560² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

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, 3409040 + ... + 3432719.

Almost surely, 2^81006426560 is an apocalyptic number.

81006426560 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81006426560 is an abundant number, since it is smaller than the sum of its proper divisors (117103576000).

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

81006426560 is a wasteful number, since it uses less digits than its factorization.

81006426560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6841813 (or 6841803 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 38.

Adding to 81006426560 its reverse (6562460018), we get a palindrome (87568886578).

The spelling of 81006426560 in words is "eighty-one billion, six million, four hundred twenty-six thousand, five hundred sixty".