21064690287 has 12 divisors (see below), whose sum is σ = 30428622640. Its totient is φ = 14042274048.

The previous prime is 21064690249. The next prime is 21064690301. The reversal of 21064690287 is 78209646012.

It is a happy number.

21064690287 is a `hidden beast` number, since 2 + 106 + 469 + 0 + 2 + 87 = 666.

It is not a de Polignac number, because 21064690287 - 2⁶ = 21064690223 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21064690217) 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, 109518 + ... + 232644.

Almost surely, 2^21064690287 is an apocalyptic number.

21064690287 is a deficient number, since it is larger than the sum of its proper divisors (9363932353).

21064690287 is a wasteful number, since it uses less digits than its factorization.

21064690287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142142 (or 142139 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 21064690287 in words is "twenty-one billion, sixty-four million, six hundred ninety thousand, two hundred eighty-seven".