21553204503415 has 32 divisors (see below), whose sum is σ = 28039041426816. Its totient is φ = 15810124838400.

The previous prime is 21553204503403. The next prime is 21553204503461. The reversal of 21553204503415 is 51430540235512.

It is not a de Polignac number, because 21553204503415 - 2¹⁵ = 21553204470647 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 396076749 + ... + 396131161.

It is an arithmetic number, because the mean of its divisors is an integer number (876220044588).

Almost surely, 2^{21553204503415} is an apocalyptic number.

21553204503415 is a deficient number, since it is larger than the sum of its proper divisors (6485836923401).

21553204503415 is a wasteful number, since it uses less digits than its factorization.

21553204503415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94939.

The product of its (nonzero) digits is 360000, while the sum is 40.

Adding to 21553204503415 its reverse (51430540235512), we get a palindrome (72983744738927).

The spelling of 21553204503415 in words is "twenty-one trillion, five hundred fifty-three billion, two hundred four million, five hundred three thousand, four hundred fifteen".