81349354620 has 120 divisors (see below), whose sum is σ = 268627405200. Its totient is φ = 20551408128.

The previous prime is 81349354607. The next prime is 81349354637. The reversal of 81349354620 is 2645394318.

81349354620 is a `hidden beast` number, since 8 + 13 + 4 + 9 + 3 + 5 + 4 + 620 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1290685 + ... + 1352244.

It is an arithmetic number, because the mean of its divisors is an integer number (2238561710).

Almost surely, 2^81349354620 is an apocalyptic number.

It is an amenable number.

81349354620 is an abundant number, since it is smaller than the sum of its proper divisors (187278050580).

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

81349354620 is a wasteful number, since it uses less digits than its factorization.

81349354620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2642969 (or 2642958 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The spelling of 81349354620 in words is "eighty-one billion, three hundred forty-nine million, three hundred fifty-four thousand, six hundred twenty".