21645460153 has 2 divisors, whose sum is σ = 21645460154. Its totient is φ = 21645460152.

The previous prime is 21645460147. The next prime is 21645460157. The reversal of 21645460153 is 35106454612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21645177129 + 283024 = 147123^2 + 532^2 .

It is a cyclic number.

It is not a de Polignac number, because 21645460153 - 2⁵ = 21645460121 is a prime.

It is a super-2 number, since 2×21645460153² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21645460157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10822730076 + 10822730077.

It is an arithmetic number, because the mean of its divisors is an integer number (10822730077).

Almost surely, 2^21645460153 is an apocalyptic number.

It is an amenable number.

21645460153 is a deficient number, since it is larger than the sum of its proper divisors (1).

21645460153 is an equidigital number, since it uses as much as digits as its factorization.

21645460153 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 86400, while the sum is 37.

The spelling of 21645460153 in words is "twenty-one billion, six hundred forty-five million, four hundred sixty thousand, one hundred fifty-three".