73031561 has 8 divisors (see below), whose sum is σ = 75250944. Its totient is φ = 70840000.

The previous prime is 73031551. The next prime is 73031597. The reversal of 73031561 is 16513037.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-73031561 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 73031561.

It is not an unprimeable number, because it can be changed into a prime (73031551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1565 + ... + 12186.

It is an arithmetic number, because the mean of its divisors is an integer number (9406368).

Almost surely, 2^73031561 is an apocalyptic number.

It is an amenable number.

73031561 is a deficient number, since it is larger than the sum of its proper divisors (2219383).

73031561 is a wasteful number, since it uses less digits than its factorization.

73031561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13911.

The product of its (nonzero) digits is 1890, while the sum is 26.

The square root of 73031561 is about 8545.8505135533. The cubic root of 73031561 is about 417.9941411540.

Adding to 73031561 its reverse (16513037), we get a palindrome (89544598).

The spelling of 73031561 in words is "seventy-three million, thirty-one thousand, five hundred sixty-one".