81919008948 has 48 divisors (see below), whose sum is σ = 225983479680. Its totient is φ = 22598346624.

The previous prime is 81919008947. The next prime is 81919009013. The reversal of 81919008948 is 84980091918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81919008947) 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, 16811811 + ... + 16816682.

It is an arithmetic number, because the mean of its divisors is an integer number (4707989160).

Almost surely, 2^81919008948 is an apocalyptic number.

It is an amenable number.

81919008948 is an abundant number, since it is smaller than the sum of its proper divisors (144064470732).

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

81919008948 is a wasteful number, since it uses less digits than its factorization.

81919008948 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33628536 (or 33628534 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 57.

The spelling of 81919008948 in words is "eighty-one billion, nine hundred nineteen million, eight thousand, nine hundred forty-eight".