21121322613545 has 32 divisors (see below), whose sum is σ = 31601391943680. Its totient is φ = 13165830901440.

The previous prime is 21121322613539. The next prime is 21121322613613. The reversal of 21121322613545 is 54531622312112.

It is not a de Polignac number, because 21121322613545 - 2⁴ = 21121322613529 is a prime.

It is a super-2 number, since 2×21121322613545² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121322613499 and 21121322613508.

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, 5741444 + ... + 8672186.

It is an arithmetic number, because the mean of its divisors is an integer number (987543498240).

Almost surely, 2^{21121322613545} is an apocalyptic number.

It is an amenable number.

21121322613545 is a deficient number, since it is larger than the sum of its proper divisors (10480069330135).

21121322613545 is a wasteful number, since it uses less digits than its factorization.

21121322613545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2949485.

The product of its digits is 86400, while the sum is 38.

Adding to 21121322613545 its reverse (54531622312112), we get a palindrome (75652944925657).

The spelling of 21121322613545 in words is "twenty-one trillion, one hundred twenty-one billion, three hundred twenty-two million, six hundred thirteen thousand, five hundred forty-five".