81029164 has 12 divisors (see below), whose sum is σ = 146375488. Its totient is φ = 39207600.

The previous prime is 81029159. The next prime is 81029189. The reversal of 81029164 is 46192018.

It is a happy number.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 326607 + ... + 326854.

Almost surely, 2^81029164 is an apocalyptic number.

It is an amenable number.

81029164 is a deficient number, since it is larger than the sum of its proper divisors (65346324).

81029164 is a wasteful number, since it uses less digits than its factorization.

81029164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 653496 (or 653494 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 81029164 is about 9001.6200764085. The cubic root of 81029164 is about 432.7267929680.

The spelling of 81029164 in words is "eighty-one million, twenty-nine thousand, one hundred sixty-four".