1621554828 has 24 divisors (see below), whose sum is σ = 3784464432. Its totient is φ = 540398784.

The previous prime is 1621554827. The next prime is 1621554833. The reversal of 1621554828 is 8284551261.

It is a self number, because there is not a number n which added to its sum of digits gives 1621554828.

It is not an unprimeable number, because it can be changed into a prime (1621554827) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54526 + ... + 78842.

It is an arithmetic number, because the mean of its divisors is an integer number (157686018).

Almost surely, 2^1621554828 is an apocalyptic number.

It is an amenable number.

1621554828 is an abundant number, since it is smaller than the sum of its proper divisors (2162909604).

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

1621554828 is a wasteful number, since it uses less digits than its factorization.

1621554828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29881 (or 29879 counting only the distinct ones).

The product of its digits is 153600, while the sum is 42.

The square root of 1621554828 is about 40268.5339688447. The cubic root of 1621554828 is about 1174.8359096041.

The spelling of 1621554828 in words is "one billion, six hundred twenty-one million, five hundred fifty-four thousand, eight hundred twenty-eight".