1618641361 has 2 divisors, whose sum is σ = 1618641362. Its totient is φ = 1618641360.

The previous prime is 1618641317. The next prime is 1618641373. The reversal of 1618641361 is 1631468161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1602480961 + 16160400 = 40031^2 + 4020^2 .

It is a cyclic number.

It is not a de Polignac number, because 1618641361 - 2¹³ = 1618633169 is a prime.

It is a super-5 number, since 5×1618641361⁵ (a number of 47 digits) contains 55555 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1618641361.

It is not a weakly prime, because it can be changed into another prime (1618641301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 809320680 + 809320681.

It is an arithmetic number, because the mean of its divisors is an integer number (809320681).

Almost surely, 2^1618641361 is an apocalyptic number.

It is an amenable number.

1618641361 is a deficient number, since it is larger than the sum of its proper divisors (1).

1618641361 is an equidigital number, since it uses as much as digits as its factorization.

1618641361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 37.

The square root of 1618641361 is about 40232.3422261245. The cubic root of 1618641361 is about 1174.1318738645.

The spelling of 1618641361 in words is "one billion, six hundred eighteen million, six hundred forty-one thousand, three hundred sixty-one".