21374325611555 has 16 divisors (see below), whose sum is σ = 29348299330560. Its totient is φ = 14639211173472.

The previous prime is 21374325611543. The next prime is 21374325611567. The reversal of 21374325611555 is 55511652347312.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21374325611543) and next prime (21374325611567).

It is a cyclic number.

It is not a de Polignac number, because 21374325611555 - 2⁸ = 21374325611299 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 363912839 + ... + 363971568.

It is an arithmetic number, because the mean of its divisors is an integer number (1834268708160).

Almost surely, 2^{21374325611555} is an apocalyptic number.

21374325611555 is a deficient number, since it is larger than the sum of its proper divisors (7973973719005).

21374325611555 is an equidigital number, since it uses as much as digits as its factorization.

21374325611555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 727885258.

The product of its digits is 3780000, while the sum is 50.

Adding to 21374325611555 its reverse (55511652347312), we get a palindrome (76885977958867).

The spelling of 21374325611555 in words is "twenty-one trillion, three hundred seventy-four billion, three hundred twenty-five million, six hundred eleven thousand, five hundred fifty-five".