21001283436 has 48 divisors (see below), whose sum is σ = 57809991680. Its totient is φ = 5806805760.

The previous prime is 21001283431. The next prime is 21001283437. The reversal of 21001283436 is 63438210012.

It is not an unprimeable number, because it can be changed into a prime (21001283431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4029901 + ... + 4035108.

Almost surely, 2^21001283436 is an apocalyptic number.

It is an amenable number.

21001283436 is an abundant number, since it is smaller than the sum of its proper divisors (36808708244).

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

21001283436 is a wasteful number, since it uses less digits than its factorization.

21001283436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8065054 (or 8065052 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

Adding to 21001283436 its reverse (63438210012), we get a palindrome (84439493448).

The spelling of 21001283436 in words is "twenty-one billion, one million, two hundred eighty-three thousand, four hundred thirty-six".