1440256221 has 20 divisors (see below), whose sum is σ = 2264732800. Its totient is φ = 909634536.

The previous prime is 1440256211. The next prime is 1440256231. The reversal of 1440256221 is 1226520441.

1440256221 is a `hidden beast` number, since 14 + 4 + 0 + 25 + 622 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (1440256211) and next prime (1440256231).

It is not a de Polignac number, because 1440256221 - 2⁷ = 1440256093 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1440256211) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 466381 + ... + 469458.

It is an arithmetic number, because the mean of its divisors is an integer number (113236640).

Almost surely, 2^1440256221 is an apocalyptic number.

It is an amenable number.

1440256221 is a deficient number, since it is larger than the sum of its proper divisors (824476579).

1440256221 is an equidigital number, since it uses as much as digits as its factorization.

1440256221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 935870 (or 935861 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 1440256221 is about 37950.7077799611. The cubic root of 1440256221 is about 1129.3102065720.

Adding to 1440256221 its reverse (1226520441), we get a palindrome (2666776662).

The spelling of 1440256221 in words is "one billion, four hundred forty million, two hundred fifty-six thousand, two hundred twenty-one".