21503212040555 has 48 divisors (see below), whose sum is σ = 32090944931136. Its totient is φ = 13539222405120.

The previous prime is 21503212040533. The next prime is 21503212040561. The reversal of 21503212040555 is 55504021230512.

It is a happy number.

It is not a de Polignac number, because 21503212040555 - 2⁶ = 21503212040491 is a prime.

It is a super-2 number, since 2×21503212040555² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25510574 + ... + 26340003.

It is an arithmetic number, because the mean of its divisors is an integer number (668561352732).

Almost surely, 2^{21503212040555} is an apocalyptic number.

21503212040555 is a deficient number, since it is larger than the sum of its proper divisors (10587732890581).

21503212040555 is a wasteful number, since it uses less digits than its factorization.

21503212040555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51850664 (or 51850647 counting only the distinct ones).

The product of its (nonzero) digits is 60000, while the sum is 35.

The spelling of 21503212040555 in words is "twenty-one trillion, five hundred three billion, two hundred twelve million, forty thousand, five hundred fifty-five".