131778413 has 4 divisors (see below), whose sum is σ = 141915228. Its totient is φ = 121641600.

The previous prime is 131778401. The next prime is 131778419. The reversal of 131778413 is 314877131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 314877131 = 8111 ⋅38821.

It can be written as a sum of positive squares in 2 ways, for example, as 33431524 + 98346889 = 5782^2 + 9917^2 .

It is a cyclic number.

It is not a de Polignac number, because 131778413 - 2¹⁸ = 131516269 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131778419) 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, 5068388 + ... + 5068413.

It is an arithmetic number, because the mean of its divisors is an integer number (35478807).

Almost surely, 2^131778413 is an apocalyptic number.

131778413 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

131778413 is a deficient number, since it is larger than the sum of its proper divisors (10136815).

131778413 is a wasteful number, since it uses less digits than its factorization.

131778413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10136814.

The product of its digits is 14112, while the sum is 35.

The square root of 131778413 is about 11479.4779062464. The cubic root of 131778413 is about 508.8792678015.

The spelling of 131778413 in words is "one hundred thirty-one million, seven hundred seventy-eight thousand, four hundred thirteen".