220161997 has 8 divisors (see below), whose sum is σ = 248459040. Its totient is φ = 193245360.

The previous prime is 220161989. The next prime is 220162001. The reversal of 220161997 is 799161022.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 220161997 - 2³ = 220161989 is a prime.

It is a super-3 number, since 3×220161997³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220161937) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 344763 + ... + 345400.

It is an arithmetic number, because the mean of its divisors is an integer number (31057380).

Almost surely, 2^220161997 is an apocalyptic number.

It is an amenable number.

220161997 is a deficient number, since it is larger than the sum of its proper divisors (28297043).

220161997 is a wasteful number, since it uses less digits than its factorization.

220161997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690203.

The product of its (nonzero) digits is 13608, while the sum is 37.

The square root of 220161997 is about 14837.8568870306. The cubic root of 220161997 is about 603.8292108450.

The spelling of 220161997 in words is "two hundred twenty million, one hundred sixty-one thousand, nine hundred ninety-seven".