20185435221 has 16 divisors (see below), whose sum is σ = 30796249728. Its totient is φ = 11520475200.

The previous prime is 20185435199. The next prime is 20185435241. The reversal of 20185435221 is 12253458102.

It is not a de Polignac number, because 20185435221 - 2⁶ = 20185435157 is a prime.

It is a super-2 number, since 2×20185435221² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20185435241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 568150 + ... + 602631.

It is an arithmetic number, because the mean of its divisors is an integer number (1924765608).

Almost surely, 2^20185435221 is an apocalyptic number.

20185435221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20185435221 is a deficient number, since it is larger than the sum of its proper divisors (10610814507).

20185435221 is a wasteful number, since it uses less digits than its factorization.

20185435221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1171612.

The product of its (nonzero) digits is 19200, while the sum is 33.

The spelling of 20185435221 in words is "twenty billion, one hundred eighty-five million, four hundred thirty-five thousand, two hundred twenty-one".