21005033415 has 16 divisors (see below), whose sum is σ = 33747511776. Its totient is φ = 11156198400.

The previous prime is 21005033393. The next prime is 21005033419. The reversal of 21005033415 is 51433050012.

It is not a de Polignac number, because 21005033415 - 2¹⁵ = 21005000647 is a prime.

It is a super-2 number, since 2×21005033415² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21005033419) 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, 2901646 + ... + 2908875.

It is an arithmetic number, because the mean of its divisors is an integer number (2109219486).

Almost surely, 2^21005033415 is an apocalyptic number.

21005033415 is a deficient number, since it is larger than the sum of its proper divisors (12742478361).

21005033415 is a wasteful number, since it uses less digits than its factorization.

21005033415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5810770.

The product of its (nonzero) digits is 1800, while the sum is 24.

Adding to 21005033415 its reverse (51433050012), we get a palindrome (72438083427).

The spelling of 21005033415 in words is "twenty-one billion, five million, thirty-three thousand, four hundred fifteen".