81401652 has 24 divisors (see below), whose sum is σ = 211041600. Its totient is φ = 27133848.

The previous prime is 81401647. The next prime is 81401653. The reversal of 81401652 is 25610418.

81401652 is a `hidden beast` number, since 8 + 1 + 4 + 0 + 1 + 652 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81401653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 376752 + ... + 376967.

It is an arithmetic number, because the mean of its divisors is an integer number (8793400).

Almost surely, 2^81401652 is an apocalyptic number.

It is an amenable number.

81401652 is an abundant number, since it is smaller than the sum of its proper divisors (129639948).

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

81401652 is a wasteful number, since it uses less digits than its factorization.

81401652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 753732 (or 753724 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 81401652 is about 9022.2864064493. The cubic root of 81401652 is about 433.3888557391.

The spelling of 81401652 in words is "eighty-one million, four hundred one thousand, six hundred fifty-two".