1644850428 has 96 divisors (see below), whose sum is σ = 4325723136. Its totient is φ = 482668032.

The previous prime is 1644850409. The next prime is 1644850447. The reversal of 1644850428 is 8240584461.

It is an interprime number because it is at equal distance from previous prime (1644850409) and next prime (1644850447).

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 1644850428.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2213425 + ... + 2214167.

It is an arithmetic number, because the mean of its divisors is an integer number (45059616).

Almost surely, 2^1644850428 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1644850428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2162861568).

1644850428 is an abundant number, since it is smaller than the sum of its proper divisors (2680872708).

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

1644850428 is a wasteful number, since it uses less digits than its factorization.

1644850428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1403 (or 1401 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 42.

The square root of 1644850428 is about 40556.7556394739. The cubic root of 1644850428 is about 1180.4351617263.

The spelling of 1644850428 in words is "one billion, six hundred forty-four million, eight hundred fifty thousand, four hundred twenty-eight".