123209217953 has 2 divisors, whose sum is σ = 123209217954. Its totient is φ = 123209217952.

The previous prime is 123209217949. The next prime is 123209217959. The reversal of 123209217953 is 359712902321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107012074129 + 16197143824 = 327127^2 + 127268^2 .

It is a cyclic number.

It is not a de Polignac number, because 123209217953 - 2² = 123209217949 is a prime.

It is a super-2 number, since 2×123209217953² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (123209217959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61604608976 + 61604608977.

It is an arithmetic number, because the mean of its divisors is an integer number (61604608977).

Almost surely, 2^123209217953 is an apocalyptic number.

It is an amenable number.

123209217953 is a deficient number, since it is larger than the sum of its proper divisors (1).

123209217953 is an equidigital number, since it uses as much as digits as its factorization.

123209217953 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 204120, while the sum is 44.

The spelling of 123209217953 in words is "one hundred twenty-three billion, two hundred nine million, two hundred seventeen thousand, nine hundred fifty-three".