81204369 has 4 divisors (see below), whose sum is σ = 108272496. Its totient is φ = 54136244.

The previous prime is 81204367. The next prime is 81204371. The reversal of 81204369 is 96340218.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (81204367) and next prime (81204371).

It is a cyclic number.

It is not a de Polignac number, because 81204369 - 2¹ = 81204367 is a prime.

It is a super-2 number, since 2×81204369² = 13188299089376322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81204367) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13534059 + ... + 13534064.

It is an arithmetic number, because the mean of its divisors is an integer number (27068124).

Almost surely, 2^81204369 is an apocalyptic number.

It is an amenable number.

81204369 is a deficient number, since it is larger than the sum of its proper divisors (27068127).

81204369 is a wasteful number, since it uses less digits than its factorization.

81204369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27068126.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 81204369 is about 9011.3466807132. The cubic root of 81204369 is about 433.0384557297.

The spelling of 81204369 in words is "eighty-one million, two hundred four thousand, three hundred sixty-nine".