245567641621 has 2 divisors, whose sum is σ = 245567641622. Its totient is φ = 245567641620.

The previous prime is 245567641601. The next prime is 245567641651. The reversal of 245567641621 is 126146765542.

245567641621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 179279415396 + 66288226225 = 423414^2 + 257465^2 .

It is a cyclic number.

It is not a de Polignac number, because 245567641621 - 2¹³ = 245567633429 is a prime.

It is a super-2 number, since 2×245567641621² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (245567641601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122783820810 + 122783820811.

It is an arithmetic number, because the mean of its divisors is an integer number (122783820811).

Almost surely, 2^245567641621 is an apocalyptic number.

It is an amenable number.

245567641621 is a deficient number, since it is larger than the sum of its proper divisors (1).

245567641621 is an equidigital number, since it uses as much as digits as its factorization.

245567641621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2419200, while the sum is 49.

The spelling of 245567641621 in words is "two hundred forty-five billion, five hundred sixty-seven million, six hundred forty-one thousand, six hundred twenty-one".