73661389 has 4 divisors (see below), whose sum is σ = 74068540. Its totient is φ = 73254240.

The previous prime is 73661383. The next prime is 73661407. The reversal of 73661389 is 98316637.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98316637 = 8513 ⋅11549.

It can be written as a sum of positive squares in 2 ways, for example, as 8584900 + 65076489 = 2930^2 + 8067^2 .

It is a cyclic number.

It is not a de Polignac number, because 73661389 - 2³ = 73661381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73661381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 203304 + ... + 203665.

It is an arithmetic number, because the mean of its divisors is an integer number (18517135).

Almost surely, 2^73661389 is an apocalyptic number.

It is an amenable number.

73661389 is a deficient number, since it is larger than the sum of its proper divisors (407151).

73661389 is a wasteful number, since it uses less digits than its factorization.

73661389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407150.

The product of its digits is 163296, while the sum is 43.

The square root of 73661389 is about 8582.6213361653. The cubic root of 73661389 is about 419.1923044939.

The spelling of 73661389 in words is "seventy-three million, six hundred sixty-one thousand, three hundred eighty-nine".