1621916 has 12 divisors (see below), whose sum is σ = 2987880. Its totient is φ = 768240.

The previous prime is 1621909. The next prime is 1621931. The reversal of 1621916 is 6191261.

It is a super-2 number, since 2×1621916² = 5261223022112, 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 (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10595 + ... + 10746.

It is an arithmetic number, because the mean of its divisors is an integer number (248990).

2^1621916 is an apocalyptic number.

It is an amenable number.

1621916 is a deficient number, since it is larger than the sum of its proper divisors (1365964).

1621916 is a wasteful number, since it uses less digits than its factorization.

1621916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21364 (or 21362 counting only the distinct ones).

The product of its digits is 648, while the sum is 26.

The square root of 1621916 is about 1273.5446596017. The cubic root of 1621916 is about 117.4923127610.

The spelling of 1621916 in words is "one million, six hundred twenty-one thousand, nine hundred sixteen".