1212651642505 has 4 divisors (see below), whose sum is σ = 1455181971012. Its totient is φ = 970121314000.

The previous prime is 1212651642493. The next prime is 1212651642509. The reversal of 1212651642505 is 5052461562121.

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 271415992576 + 941235649929 = 520976^2 + 970173^2 .

It is not a de Polignac number, because 1212651642505 - 2¹⁵ = 1212651609737 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1212651642509) 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, 121265164246 + ... + 121265164255.

It is an arithmetic number, because the mean of its divisors is an integer number (363795492753).

Almost surely, 2^{1212651642505} is an apocalyptic number.

It is an amenable number.

1212651642505 is a deficient number, since it is larger than the sum of its proper divisors (242530328507).

1212651642505 is an equidigital number, since it uses as much as digits as its factorization.

1212651642505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242530328506.

The product of its (nonzero) digits is 144000, while the sum is 40.

The spelling of 1212651642505 in words is "one trillion, two hundred twelve billion, six hundred fifty-one million, six hundred forty-two thousand, five hundred five".