21404152015 has 24 divisors (see below), whose sum is σ = 27576083808. Its totient is φ = 15936085440.

The previous prime is 21404152013. The next prime is 21404152019. The reversal of 21404152015 is 51025140412.

It is not a de Polignac number, because 21404152015 - 2¹ = 21404152013 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 (21404152013) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11491 + ... + 207220.

It is an arithmetic number, because the mean of its divisors is an integer number (1149003492).

Almost surely, 2^21404152015 is an apocalyptic number.

21404152015 is a deficient number, since it is larger than the sum of its proper divisors (6171931793).

21404152015 is a wasteful number, since it uses less digits than its factorization.

21404152015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218799 (or 218776 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 25.

Adding to 21404152015 its reverse (51025140412), we get a palindrome (72429292427).

The spelling of 21404152015 in words is "twenty-one billion, four hundred four million, one hundred fifty-two thousand, fifteen".