285978111989 has 8 divisors (see below), whose sum is σ = 287759592120. Its totient is φ = 284198846400.

The previous prime is 285978111983. The next prime is 285978112019. The reversal of 285978111989 is 989111879582.

It can be written as a sum of positive squares in 4 ways, for example, as 53107202500 + 232870909489 = 230450^2 + 482567^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 285978111989 - 2⁴ = 285978111973 is a prime.

It is a super-2 number, since 2×285978111989² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285978111983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 294182 + ... + 811479.

It is an arithmetic number, because the mean of its divisors is an integer number (35969949015).

Almost surely, 2^285978111989 is an apocalyptic number.

It is an amenable number.

285978111989 is a deficient number, since it is larger than the sum of its proper divisors (1781480131).

285978111989 is a wasteful number, since it uses less digits than its factorization.

285978111989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1107271.

The product of its digits is 26127360, while the sum is 68.

The spelling of 285978111989 in words is "two hundred eighty-five billion, nine hundred seventy-eight million, one hundred eleven thousand, nine hundred eighty-nine".