81229952 has 16 divisors (see below), whose sum is σ = 161825550. Its totient is φ = 40614912.

The previous prime is 81229949. The next prime is 81229963. The reversal of 81229952 is 25992218.

It can be written as a sum of positive squares in only one way, i.e., 65674816 + 15555136 = 8104^2 + 3944^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 317177 + ... + 317432.

Almost surely, 2^81229952 is an apocalyptic number.

It is an amenable number.

81229952 is a deficient number, since it is larger than the sum of its proper divisors (80595598).

81229952 is an equidigital number, since it uses as much as digits as its factorization.

81229952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634623 (or 634611 counting only the distinct ones).

The product of its digits is 25920, while the sum is 38.

The square root of 81229952 is about 9012.7660570992. The cubic root of 81229952 is about 433.0839264343.

The spelling of 81229952 in words is "eighty-one million, two hundred twenty-nine thousand, nine hundred fifty-two".