81373215380 has 48 divisors (see below), whose sum is σ = 172712082816. Its totient is φ = 32201850240.

The previous prime is 81373215337. The next prime is 81373215383. The reversal of 81373215380 is 8351237318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81373215383) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1594865 + ... + 1645095.

It is an arithmetic number, because the mean of its divisors is an integer number (3598168392).

Almost surely, 2^81373215380 is an apocalyptic number.

It is an amenable number.

81373215380 is an abundant number, since it is smaller than the sum of its proper divisors (91338867436).

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

81373215380 is a wasteful number, since it uses less digits than its factorization.

81373215380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51104 (or 51102 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 41.

The spelling of 81373215380 in words is "eighty-one billion, three hundred seventy-three million, two hundred fifteen thousand, three hundred eighty".