153440221 has 12 divisors (see below), whose sum is σ = 173220796. Its totient is φ = 135717120.

The previous prime is 153440201. The next prime is 153440227. The reversal of 153440221 is 122044351.

It can be written as a sum of positive squares in 2 ways, for example, as 138532900 + 14907321 = 11770^2 + 3861^2 .

It is not a de Polignac number, because 153440221 - 2⁷ = 153440093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 153440192 and 153440201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (153440227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12660 + ... + 21613.

Almost surely, 2^153440221 is an apocalyptic number.

153440221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

153440221 is a deficient number, since it is larger than the sum of its proper divisors (19780575).

153440221 is a wasteful number, since it uses less digits than its factorization.

153440221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34332 (or 34321 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 153440221 is about 12387.0989743362. The cubic root of 153440221 is about 535.3605988907.

Adding to 153440221 its reverse (122044351), we get a palindrome (275484572).

The spelling of 153440221 in words is "one hundred fifty-three million, four hundred forty thousand, two hundred twenty-one".