1421839728 has 120 divisors (see below), whose sum is σ = 4074117216. Its totient is φ = 462758400.

The previous prime is 1421839687. The next prime is 1421839729. The reversal of 1421839728 is 8279381241.

It is a happy number.

It is a super-2 number, since 2×1421839728² = 4043256424238227968, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1421839729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1378573 + ... + 1379603.

Almost surely, 2^1421839728 is an apocalyptic number.

1421839728 is a gapful number since it is divisible by the number (18) 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 1421839728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2037058608).

1421839728 is an abundant number, since it is smaller than the sum of its proper divisors (2652277488).

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

1421839728 is a wasteful number, since it uses less digits than its factorization.

1421839728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1263 (or 1254 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 1421839728 is about 37707.2901174295. The cubic root of 1421839728 is about 1124.4760629920.

The spelling of 1421839728 in words is "one billion, four hundred twenty-one million, eight hundred thirty-nine thousand, seven hundred twenty-eight".