145421440 has 64 divisors (see below), whose sum is σ = 365976000. Its totient is φ = 55102464.

The previous prime is 145421413. The next prime is 145421473. The reversal of 145421440 is 44124541.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×145421440² = 42294790423347200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6181 + ... + 18139.

It is an arithmetic number, because the mean of its divisors is an integer number (5718375).

Almost surely, 2^145421440 is an apocalyptic number.

145421440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 145421440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (182988000).

145421440 is an abundant number, since it is smaller than the sum of its proper divisors (220554560).

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

145421440 is a wasteful number, since it uses less digits than its factorization.

145421440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11997 (or 11985 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 25.

The square root of 145421440 is about 12059.0812253670. The cubic root of 145421440 is about 525.8672770138.

Adding to 145421440 its reverse (44124541), we get a palindrome (189545981).

The spelling of 145421440 in words is "one hundred forty-five million, four hundred twenty-one thousand, four hundred forty".