1212138085 has 16 divisors (see below), whose sum is σ = 1506178800. Its totient is φ = 935366656.

The previous prime is 1212138077. The next prime is 1212138119. The reversal of 1212138085 is 5808312121.

It can be written as a sum of positive squares in 8 ways, for example, as 253987969 + 958150116 = 15937^2 + 30954^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212138085 - 2³ = 1212138077 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 173031 + ... + 179899.

It is an arithmetic number, because the mean of its divisors is an integer number (94136175).

Almost surely, 2^1212138085 is an apocalyptic number.

It is an amenable number.

1212138085 is a deficient number, since it is larger than the sum of its proper divisors (294040715).

1212138085 is a wasteful number, since it uses less digits than its factorization.

1212138085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8120.

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 1212138085 is about 34815.7735085694. The cubic root of 1212138085 is about 1066.2295115649.

The spelling of 1212138085 in words is "one billion, two hundred twelve million, one hundred thirty-eight thousand, eighty-five".