1215065889 has 12 divisors (see below), whose sum is σ = 1760071716. Its totient is φ = 807747072.

The previous prime is 1215065881. The next prime is 1215065897. The reversal of 1215065889 is 9885605121.

It is a happy number.

1215065889 is a `hidden beast` number, since 12 + 1 + 50 + 6 + 588 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (1215065881) and next prime (1215065897).

It can be written as a sum of positive squares in 2 ways, for example, as 256544289 + 958521600 = 16017^2 + 30960^2 .

It is not a de Polignac number, because 1215065889 - 2³ = 1215065881 is a prime.

It is a super-2 number, since 2×1215065889² = 2952770229222720642, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1215065881) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 188052 + ... + 194405.

It is an arithmetic number, because the mean of its divisors is an integer number (146672643).

Almost surely, 2^1215065889 is an apocalyptic number.

It is an amenable number.

1215065889 is a deficient number, since it is larger than the sum of its proper divisors (545005827).

1215065889 is a wasteful number, since it uses less digits than its factorization.

1215065889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382816 (or 382813 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 45.

The square root of 1215065889 is about 34857.7952400894. The cubic root of 1215065889 is about 1067.0872798990.

The spelling of 1215065889 in words is "one billion, two hundred fifteen million, sixty-five thousand, eight hundred eighty-nine".