1242697820885 has 4 divisors (see below), whose sum is σ = 1491237385068. Its totient is φ = 994158256704.

The previous prime is 1242697820779. The next prime is 1242697820891. The reversal of 1242697820885 is 5880287962421.

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

It can be written as a sum of positive squares in 2 ways, for example, as 942526422244 + 300171398641 = 970838^2 + 547879^2 .

It is a cyclic number.

It is not a de Polignac number, because 1242697820885 - 2¹⁰ = 1242697819861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124269782084 + ... + 124269782093.

It is an arithmetic number, because the mean of its divisors is an integer number (372809346267).

Almost surely, 2^{1242697820885} is an apocalyptic number.

It is an amenable number.

1242697820885 is a deficient number, since it is larger than the sum of its proper divisors (248539564183).

1242697820885 is an equidigital number, since it uses as much as digits as its factorization.

1242697820885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248539564182.

The product of its (nonzero) digits is 30965760, while the sum is 62.

The spelling of 1242697820885 in words is "one trillion, two hundred forty-two billion, six hundred ninety-seven million, eight hundred twenty thousand, eight hundred eighty-five".