81933201 has 40 divisors (see below), whose sum is σ = 141645504. Its totient is φ = 46228320.

The previous prime is 81933197. The next prime is 81933233. The reversal of 81933201 is 10233918.

It is not a de Polignac number, because 81933201 - 2² = 81933197 is a prime.

It is a super-2 number, since 2×81933201² = 13426098852212802, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (81933001) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 46191 + ... + 47931.

Almost surely, 2^81933201 is an apocalyptic number.

81933201 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

It is an amenable number.

81933201 is a deficient number, since it is larger than the sum of its proper divisors (59712303).

81933201 is a wasteful number, since it uses less digits than its factorization.

81933201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1843 (or 1834 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 81933201 is about 9051.6960289219. The cubic root of 81933201 is about 434.3301461958.

The spelling of 81933201 in words is "eighty-one million, nine hundred thirty-three thousand, two hundred one".