1621289688 has 32 divisors (see below), whose sum is σ = 4229452800. Its totient is φ = 516932768.

The previous prime is 1621289687. The next prime is 1621289701. The reversal of 1621289688 is 8869821261.

It is a self number, because there is not a number n which added to its sum of digits gives 1621289688.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1621289687) 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, 1468008 + ... + 1469111.

It is an arithmetic number, because the mean of its divisors is an integer number (132170400).

Almost surely, 2^1621289688 is an apocalyptic number.

It is an amenable number.

1621289688 is an abundant number, since it is smaller than the sum of its proper divisors (2608163112).

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

1621289688 is a wasteful number, since it uses less digits than its factorization.

1621289688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2937151 (or 2937147 counting only the distinct ones).

The product of its digits is 663552, while the sum is 51.

The square root of 1621289688 is about 40265.2416856027. The cubic root of 1621289688 is about 1174.7718737444.

The spelling of 1621289688 in words is "one billion, six hundred twenty-one million, two hundred eighty-nine thousand, six hundred eighty-eight".