1617657461221 has 2 divisors, whose sum is σ = 1617657461222. Its totient is φ = 1617657461220.

The previous prime is 1617657461197. The next prime is 1617657461269. The reversal of 1617657461221 is 1221647567161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1217425356900 + 400232104321 = 1103370^2 + 632639^2 .

It is a cyclic number.

It is not a de Polignac number, because 1617657461221 - 2¹³ = 1617657453029 is a prime.

It is a super-2 number, since 2×1617657461221² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1617657461621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 808828730610 + 808828730611.

It is an arithmetic number, because the mean of its divisors is an integer number (808828730611).

Almost surely, 2^{1617657461221} is an apocalyptic number.

It is an amenable number.

1617657461221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1617657461221 is an equidigital number, since it uses as much as digits as its factorization.

1617657461221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 846720, while the sum is 49.

The spelling of 1617657461221 in words is "one trillion, six hundred seventeen billion, six hundred fifty-seven million, four hundred sixty-one thousand, two hundred twenty-one".