49661591581 has 12 divisors (see below), whose sum is σ = 61167819708. Its totient is φ = 40063132032.

The previous prime is 49661591531. The next prime is 49661591593. The reversal of 49661591581 is 18519516694.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 23823922500 + 25837669081 = 154350^2 + 160741^2 .

It is not a de Polignac number, because 49661591581 - 2⁷ = 49661591453 is a prime.

It is a super-2 number, since 2×49661591581² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (49661591521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29808046 + ... + 29809711.

It is an arithmetic number, because the mean of its divisors is an integer number (5097318309).

Almost surely, 2^49661591581 is an apocalyptic number.

It is an amenable number.

49661591581 is a deficient number, since it is larger than the sum of its proper divisors (11506228127).

49661591581 is a wasteful number, since it uses less digits than its factorization.

49661591581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59617788 (or 59617781 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 55.

The spelling of 49661591581 in words is "forty-nine billion, six hundred sixty-one million, five hundred ninety-one thousand, five hundred eighty-one".