73431540 has 144 divisors (see below), whose sum is σ = 274205568. Its totient is φ = 15489792.

The previous prime is 73431499. The next prime is 73431557. The reversal of 73431540 is 4513437.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 14139 + ... + 18621.

Almost surely, 2^73431540 is an apocalyptic number.

73431540 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 73431540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137102784).

73431540 is an abundant number, since it is smaller than the sum of its proper divisors (200774028).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

73431540 is a wasteful number, since it uses less digits than its factorization.

73431540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4518 (or 4513 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 27.

The square root of 73431540 is about 8569.2205013058. The cubic root of 73431540 is about 418.7558419026.

Adding to 73431540 its reverse (4513437), we get a palindrome (77944977).

The spelling of 73431540 in words is "seventy-three million, four hundred thirty-one thousand, five hundred forty".