81954624 has 56 divisors (see below), whose sum is σ = 218610688. Its totient is φ = 27095040.

The previous prime is 81954583. The next prime is 81954629. The reversal of 81954624 is 42645918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81954629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22704 + ... + 26064.

Almost surely, 2^81954624 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81954624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109305344).

81954624 is an abundant number, since it is smaller than the sum of its proper divisors (136656064).

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

81954624 is a wasteful number, since it uses less digits than its factorization.

81954624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3503 (or 3493 counting only the distinct ones).

The product of its digits is 69120, while the sum is 39.

The square root of 81954624 is about 9052.8793209674. The cubic root of 81954624 is about 434.3679975339.

The spelling of 81954624 in words is "eighty-one million, nine hundred fifty-four thousand, six hundred twenty-four".