81543950370 has 32 divisors (see below), whose sum is σ = 217450535040. Its totient is φ = 21745053360.

The previous prime is 81543950333. The next prime is 81543950393. The reversal of 81543950370 is 7305934518.

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

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, 151007046 + ... + 151007585.

It is an arithmetic number, because the mean of its divisors is an integer number (6795329220).

Almost surely, 2^81543950370 is an apocalyptic number.

81543950370 is an abundant number, since it is smaller than the sum of its proper divisors (135906584670).

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

81543950370 is a wasteful number, since it uses less digits than its factorization.

81543950370 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302014647 (or 302014641 counting only the distinct ones).

The product of its (nonzero) digits is 453600, while the sum is 45.

The spelling of 81543950370 in words is "eighty-one billion, five hundred forty-three million, nine hundred fifty thousand, three hundred seventy".