243400120131 has 32 divisors (see below), whose sum is σ = 371892238848. Its totient is φ = 138712492800.

The previous prime is 243400120123. The next prime is 243400120151. The reversal of 243400120131 is 131021004342.

It is not a de Polignac number, because 243400120131 - 2³ = 243400120123 is a prime.

It is a super-2 number, since 2×243400120131² (a number of 24 digits) contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 243400120098 and 243400120107.

It is not an unprimeable number, because it can be changed into a prime (243400120111) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12164271 + ... + 12184263.

It is an arithmetic number, because the mean of its divisors is an integer number (11621632464).

Almost surely, 2^243400120131 is an apocalyptic number.

243400120131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

243400120131 is a deficient number, since it is larger than the sum of its proper divisors (128492118717).

243400120131 is a wasteful number, since it uses less digits than its factorization.

243400120131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21531.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 243400120131 its reverse (131021004342), we get a palindrome (374421124473).

The spelling of 243400120131 in words is "two hundred forty-three billion, four hundred million, one hundred twenty thousand, one hundred thirty-one".