21154533221445 has 32 divisors (see below), whose sum is σ = 36455878956672. Its totient is φ = 10413113448192.

The previous prime is 21154533221411. The next prime is 21154533221527. The reversal of 21154533221445 is 54412233545112.

It is not a de Polignac number, because 21154533221445 - 2¹⁴ = 21154533205061 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21154533221397 and 21154533221406.

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, 5998482 + ... + 8848211.

It is an arithmetic number, because the mean of its divisors is an integer number (1139246217396).

Almost surely, 2^{21154533221445} is an apocalyptic number.

It is an amenable number.

21154533221445 is a deficient number, since it is larger than the sum of its proper divisors (15301345735227).

21154533221445 is a wasteful number, since it uses less digits than its factorization.

21154533221445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14854021.

The product of its digits is 576000, while the sum is 42.

Adding to 21154533221445 its reverse (54412233545112), we get a palindrome (75566766766557).

The spelling of 21154533221445 in words is "twenty-one trillion, one hundred fifty-four billion, five hundred thirty-three million, two hundred twenty-one thousand, four hundred forty-five".