21765420545630 has 16 divisors (see below), whose sum is σ = 41239744192080. Its totient is φ = 8247948838272.

The previous prime is 21765420545629. The next prime is 21765420545639. The reversal of 21765420545630 is 3654502456712.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21765420545639) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57277422299 + ... + 57277422678.

It is an arithmetic number, because the mean of its divisors is an integer number (2577484012005).

Almost surely, 2^{21765420545630} is an apocalyptic number.

21765420545630 is a deficient number, since it is larger than the sum of its proper divisors (19474323646450).

21765420545630 is a wasteful number, since it uses less digits than its factorization.

21765420545630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114554845003.

The product of its (nonzero) digits is 6048000, while the sum is 50.

The spelling of 21765420545630 in words is "twenty-one trillion, seven hundred sixty-five billion, four hundred twenty million, five hundred forty-five thousand, six hundred thirty".