1243142121 has 32 divisors (see below), whose sum is σ = 1811134080. Its totient is φ = 753882624.

The previous prime is 1243142107. The next prime is 1243142137. The reversal of 1243142121 is 1212413421.

It is not a de Polignac number, because 1243142121 - 2¹⁵ = 1243109353 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1243142141) 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, 1933026 + ... + 1933668.

It is an arithmetic number, because the mean of its divisors is an integer number (56597940).

Almost surely, 2^1243142121 is an apocalyptic number.

It is an amenable number.

1243142121 is a deficient number, since it is larger than the sum of its proper divisors (567991959).

1243142121 is a wasteful number, since it uses less digits than its factorization.

1243142121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1305.

The product of its digits is 384, while the sum is 21.

The square root of 1243142121 is about 35258.2206159074. The cubic root of 1243142121 is about 1075.2437510362.

Adding to 1243142121 its reverse (1212413421), we get a palindrome (2455555542).

The spelling of 1243142121 in words is "one billion, two hundred forty-three million, one hundred forty-two thousand, one hundred twenty-one".