131634821 has 4 divisors (see below), whose sum is σ = 131657772. Its totient is φ = 131611872.

The previous prime is 131634787. The next prime is 131634823. The reversal of 131634821 is 128436131.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 128436131 = 31 ⋅4143101.

It can be written as a sum of positive squares in 2 ways, for example, as 74632321 + 57002500 = 8639^2 + 7550^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131634821 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 (131634823) 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, 5435 + ... + 17111.

It is an arithmetic number, because the mean of its divisors is an integer number (32914443).

Almost surely, 2^131634821 is an apocalyptic number.

It is an amenable number.

131634821 is a deficient number, since it is larger than the sum of its proper divisors (22951).

131634821 is a wasteful number, since it uses less digits than its factorization.

131634821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22950.

The product of its digits is 3456, while the sum is 29.

The square root of 131634821 is about 11473.2219101698. The cubic root of 131634821 is about 508.6943676427.

The spelling of 131634821 in words is "one hundred thirty-one million, six hundred thirty-four thousand, eight hundred twenty-one".