221402340 has 36 divisors (see below), whose sum is σ = 671587644. Its totient is φ = 59040576.

The previous prime is 221402329. The next prime is 221402381. The reversal of 221402340 is 43204122.

221402340 is a `hidden beast` number, since 221 + 402 + 3 + 40 = 666.

221402340 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 73925604 + 147476736 = 8598^2 + 12144^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

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 in 11 ways as a sum of consecutive naturals, for example, 614827 + ... + 615186.

Almost surely, 2^221402340 is an apocalyptic number.

221402340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221402340 is an abundant number, since it is smaller than the sum of its proper divisors (450185304).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221402340 is a wasteful number, since it uses less digits than its factorization.

221402340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1230028 (or 1230023 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 221402340 is about 14879.5947525462. The cubic root of 221402340 is about 604.9610338494.

Adding to 221402340 its reverse (43204122), we get a palindrome (264606462).

The spelling of 221402340 in words is "two hundred twenty-one million, four hundred two thousand, three hundred forty".