1242439881 has 4 divisors (see below), whose sum is σ = 1656586512. Its totient is φ = 828293252.

The previous prime is 1242439867. The next prime is 1242439897. The reversal of 1242439881 is 1889342421.

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 1242439881 - 2¹⁵ = 1242407113 is a prime.

It is a super-2 number, since 2×1242439881² = 3087313715798588322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1242439831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 207073311 + ... + 207073316.

It is an arithmetic number, because the mean of its divisors is an integer number (414146628).

Almost surely, 2^1242439881 is an apocalyptic number.

It is an amenable number.

1242439881 is a deficient number, since it is larger than the sum of its proper divisors (414146631).

1242439881 is an equidigital number, since it uses as much as digits as its factorization.

1242439881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 414146630.

The product of its digits is 110592, while the sum is 42.

The square root of 1242439881 is about 35248.2606804932. The cubic root of 1242439881 is about 1075.0412476692.

The spelling of 1242439881 in words is "one billion, two hundred forty-two million, four hundred thirty-nine thousand, eight hundred eighty-one".