81001426020 has 48 divisors (see below), whose sum is σ = 226995265728. Its totient is φ = 21582163840.

The previous prime is 81001426001. The next prime is 81001426049. The reversal of 81001426020 is 2062410018.

It is a super-2 number, since 2×81001426020² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 497451 + ... + 639890.

It is an arithmetic number, because the mean of its divisors is an integer number (4729068036).

Almost surely, 2^81001426020 is an apocalyptic number.

It is an amenable number.

81001426020 is an abundant number, since it is smaller than the sum of its proper divisors (145993839708).

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

81001426020 is a wasteful number, since it uses less digits than its factorization.

81001426020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1138540 (or 1138538 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

Adding to 81001426020 its reverse (2062410018), we get a palindrome (83063836038).

The spelling of 81001426020 in words is "eighty-one billion, one million, four hundred twenty-six thousand, twenty".