21001283408 has 40 divisors (see below), whose sum is σ = 46511784960. Its totient is φ = 8998819200.

The previous prime is 21001283393. The next prime is 21001283419. The reversal of 21001283408 is 80438210012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 690833 + ... + 720591.

It is an arithmetic number, because the mean of its divisors is an integer number (1162794624).

Almost surely, 2^21001283408 is an apocalyptic number.

21001283408 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21001283408 is an abundant number, since it is smaller than the sum of its proper divisors (25510501552).

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

21001283408 is a wasteful number, since it uses less digits than its factorization.

21001283408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36075 (or 36069 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The spelling of 21001283408 in words is "twenty-one billion, one million, two hundred eighty-three thousand, four hundred eight".