131405421 has 16 divisors (see below), whose sum is σ = 200412800. Its totient is φ = 75022848.

The previous prime is 131405413. The next prime is 131405459. The reversal of 131405421 is 124504131.

It is not a de Polignac number, because 131405421 - 2³ = 131405413 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131405821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31845 + ... + 35733.

It is an arithmetic number, because the mean of its divisors is an integer number (12525800).

Almost surely, 2^131405421 is an apocalyptic number.

It is an amenable number.

131405421 is a deficient number, since it is larger than the sum of its proper divisors (69007379).

131405421 is a wasteful number, since it uses less digits than its factorization.

131405421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5508.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 131405421 is about 11463.2203590440. The cubic root of 131405421 is about 508.3986952652.

Adding to 131405421 its reverse (124504131), we get a palindrome (255909552).

The spelling of 131405421 in words is "one hundred thirty-one million, four hundred five thousand, four hundred twenty-one".