81207145420 has 12 divisors (see below), whose sum is σ = 170535005424. Its totient is φ = 32482858160.

The previous prime is 81207145417. The next prime is 81207145429. The reversal of 81207145420 is 2454170218.

It is not an unprimeable number, because it can be changed into a prime (81207145429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2030178616 + ... + 2030178655.

It is an arithmetic number, because the mean of its divisors is an integer number (14211250452).

Almost surely, 2^81207145420 is an apocalyptic number.

It is an amenable number.

81207145420 is an abundant number, since it is smaller than the sum of its proper divisors (89327860004).

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

81207145420 is a wasteful number, since it uses less digits than its factorization.

81207145420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4060357280 (or 4060357278 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 34.

The spelling of 81207145420 in words is "eighty-one billion, two hundred seven million, one hundred forty-five thousand, four hundred twenty".