1212771385081 has 27 divisors (see below), whose sum is σ = 1291930065741. Its totient is φ = 1138296542688.

The previous prime is 1212771385069. The next prime is 1212771385087. The reversal of 1212771385081 is 1805831772121.

The square root of 1212771385081 is 1101259.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 520214545081 + 692556840000 = 721259^2 + 832200^2 .

It is not a de Polignac number, because 1212771385081 - 2¹⁹ = 1212770860793 is a prime.

It is a super-2 number, since 2×1212771385081² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1212771385087) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 3117664035 + ... + 3117664423.

Almost surely, 2^{1212771385081} is an apocalyptic number.

1212771385081 is the 1101259-th square number.

1212771385081 is the 550630-th centered octagonal number.

It is an amenable number.

1212771385081 is a deficient number, since it is larger than the sum of its proper divisors (79158680660).

1212771385081 is an frugal number, since it uses more digits than its factorization.

1212771385081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1114 (or 557 counting only the distinct ones).

The product of its (nonzero) digits is 188160, while the sum is 46.

The spelling of 1212771385081 in words is "one trillion, two hundred twelve billion, seven hundred seventy-one million, three hundred eighty-five thousand, eighty-one".