217620061 has 4 divisors (see below), whose sum is σ = 217654272. Its totient is φ = 217585852.

The previous prime is 217620047. The next prime is 217620071. The reversal of 217620061 is 160026712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 217620061 - 2²³ = 209231453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217620071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4435 + ... + 21328.

It is an arithmetic number, because the mean of its divisors is an integer number (54413568).

Almost surely, 2^217620061 is an apocalyptic number.

It is an amenable number.

217620061 is a deficient number, since it is larger than the sum of its proper divisors (34211).

217620061 is an equidigital number, since it uses as much as digits as its factorization.

217620061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34210.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 217620061 is about 14751.9510912964. The cubic root of 217620061 is about 601.4963217481.

Adding to 217620061 its reverse (160026712), we get a palindrome (377646773).

The spelling of 217620061 in words is "two hundred seventeen million, six hundred twenty thousand, sixty-one".