1071215861 has 2 divisors, whose sum is σ = 1071215862. Its totient is φ = 1071215860.

The previous prime is 1071215857. The next prime is 1071215879. The reversal of 1071215861 is 1685121701.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 631516900 + 439698961 = 25130^2 + 20969^2 .

It is an emirp because it is prime and its reverse (1685121701) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1071215861 - 2² = 1071215857 is a prime.

It is a super-2 number, since 2×1071215861² = 2295006841715942642, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1071215161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 535607930 + 535607931.

It is an arithmetic number, because the mean of its divisors is an integer number (535607931).

Almost surely, 2^1071215861 is an apocalyptic number.

It is an amenable number.

1071215861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1071215861 is an equidigital number, since it uses as much as digits as its factorization.

1071215861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3360, while the sum is 32.

The square root of 1071215861 is about 32729.4341686501. The cubic root of 1071215861 is about 1023.1963874953.

The spelling of 1071215861 in words is "one billion, seventy-one million, two hundred fifteen thousand, eight hundred sixty-one".