1641562217 has 2 divisors, whose sum is σ = 1641562218. Its totient is φ = 1641562216.

The previous prime is 1641562213. The next prime is 1641562271. The reversal of 1641562217 is 7122651461.

Together with next prime (1641562271) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1568476816 + 73085401 = 39604^2 + 8549^2 .

It is a cyclic number.

It is not a de Polignac number, because 1641562217 - 2² = 1641562213 is a prime.

It is not a weakly prime, because it can be changed into another prime (1641562213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820781108 + 820781109.

It is an arithmetic number, because the mean of its divisors is an integer number (820781109).

Almost surely, 2^1641562217 is an apocalyptic number.

It is an amenable number.

1641562217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641562217 is an equidigital number, since it uses as much as digits as its factorization.

1641562217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20160, while the sum is 35.

The square root of 1641562217 is about 40516.1969710880. The cubic root of 1641562217 is about 1179.6480366070.

The spelling of 1641562217 in words is "one billion, six hundred forty-one million, five hundred sixty-two thousand, two hundred seventeen".