21011210964 has 54 divisors (see below), whose sum is σ = 55006341390. Its totient is φ = 6762219072.

The previous prime is 21011210963. The next prime is 21011211017. The reversal of 21011210964 is 46901211012.

It can be written as a sum of positive squares in 3 ways, for example, as 10765722564 + 10245488400 = 103758^2 + 101220^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011210963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 316719 + ... + 377270.

Almost surely, 2^21011210964 is an apocalyptic number.

It is an amenable number.

21011210964 is an abundant number, since it is smaller than the sum of its proper divisors (33995130426).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21011210964 is a wasteful number, since it uses less digits than its factorization.

21011210964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694057 (or 694023 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

Adding to 21011210964 its reverse (46901211012), we get a palindrome (67912421976).

The spelling of 21011210964 in words is "twenty-one billion, eleven million, two hundred ten thousand, nine hundred sixty-four".