1621040688 has 100 divisors (see below), whose sum is σ = 4700333088. Its totient is φ = 539360640.

The previous prime is 1621040653. The next prime is 1621040717. The reversal of 1621040688 is 8860401261.

1621040688 is a `hidden beast` number, since 162 + 10 + 406 + 88 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1179970 + ... + 1181342.

Almost surely, 2^1621040688 is an apocalyptic number.

1621040688 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1621040688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2350166544).

1621040688 is an abundant number, since it is smaller than the sum of its proper divisors (3079292400).

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

1621040688 is a wasteful number, since it uses less digits than its factorization.

1621040688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2304 (or 2289 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 1621040688 is about 40262.1495700366. The cubic root of 1621040688 is about 1174.7117296145.

The spelling of 1621040688 in words is "one billion, six hundred twenty-one million, forty thousand, six hundred eighty-eight".