1621746844 has 24 divisors (see below), whose sum is σ = 2912249088. Its totient is φ = 789840240.

The previous prime is 1621746823. The next prime is 1621746851. The reversal of 1621746844 is 4486471261.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1621746844.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19227 + ... + 60109.

It is an arithmetic number, because the mean of its divisors is an integer number (121343712).

Almost surely, 2^1621746844 is an apocalyptic number.

It is an amenable number.

1621746844 is a deficient number, since it is larger than the sum of its proper divisors (1290502244).

1621746844 is a wasteful number, since it uses less digits than its factorization.

1621746844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41145 (or 41143 counting only the distinct ones).

The product of its digits is 258048, while the sum is 43.

The square root of 1621746844 is about 40270.9180923405. The cubic root of 1621746844 is about 1174.8822804050.

The spelling of 1621746844 in words is "one billion, six hundred twenty-one million, seven hundred forty-six thousand, eight hundred forty-four".