1231432401421 has 4 divisors (see below), whose sum is σ = 1231436268832. Its totient is φ = 1231428534012.

The previous prime is 1231432401401. The next prime is 1231432401469. The reversal of 1231432401421 is 1241042341321.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1231432401421 - 2²⁹ = 1230895530509 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1231432401421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231432401401) 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, 1408545 + ... + 2108758.

It is an arithmetic number, because the mean of its divisors is an integer number (307859067208).

Almost surely, 2^{1231432401421} is an apocalyptic number.

It is an amenable number.

1231432401421 is a deficient number, since it is larger than the sum of its proper divisors (3867411).

1231432401421 is an equidigital number, since it uses as much as digits as its factorization.

1231432401421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3867410.

The product of its (nonzero) digits is 4608, while the sum is 28.

Adding to 1231432401421 its reverse (1241042341321), we get a palindrome (2472474742742).

The spelling of 1231432401421 in words is "one trillion, two hundred thirty-one billion, four hundred thirty-two million, four hundred one thousand, four hundred twenty-one".