1231401111 has 4 divisors (see below), whose sum is σ = 1641868152. Its totient is φ = 820934072.

The previous prime is 1231401097. The next prime is 1231401121. The reversal of 1231401111 is 1111041321.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1231401111 - 2⁷ = 1231400983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231401121) 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, 205233516 + ... + 205233521.

It is an arithmetic number, because the mean of its divisors is an integer number (410467038).

Almost surely, 2^1231401111 is an apocalyptic number.

1231401111 is a deficient number, since it is larger than the sum of its proper divisors (410467041).

1231401111 is an equidigital number, since it uses as much as digits as its factorization.

1231401111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410467040.

The product of its (nonzero) digits is 24, while the sum is 15.

The square root of 1231401111 is about 35091.3252955770. The cubic root of 1231401111 is about 1071.8479467892.

Adding to 1231401111 its reverse (1111041321), we get a palindrome (2342442432).

It can be divided in two parts, 123140 and 1111, that added together give a triangular number (124251 = T₄₉₈).

The spelling of 1231401111 in words is "one billion, two hundred thirty-one million, four hundred one thousand, one hundred eleven".