1621204016 has 20 divisors (see below), whose sum is σ = 3148775400. Its totient is φ = 808616832.

The previous prime is 1621204009. The next prime is 1621204019. The reversal of 1621204016 is 6104021261.

It is a super-2 number, since 2×1621204016² = 5256604922989056512, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1621203982 and 1621204000.

It is not an unprimeable number, because it can be changed into a prime (1621204019) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 117326 + ... + 130413.

It is an arithmetic number, because the mean of its divisors is an integer number (157438770).

Almost surely, 2^1621204016 is an apocalyptic number.

1621204016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1621204016 is a deficient number, since it is larger than the sum of its proper divisors (1527571384).

1621204016 is a wasteful number, since it uses less digits than its factorization.

1621204016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248156 (or 248150 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 1621204016 is about 40264.1778259534. The cubic root of 1621204016 is about 1174.7511809940.

Adding to 1621204016 its reverse (6104021261), we get a palindrome (7725225277).

The spelling of 1621204016 in words is "one billion, six hundred twenty-one million, two hundred four thousand, sixteen".