1621640224 has 12 divisors (see below), whose sum is σ = 3192604254. Its totient is φ = 810820096.

The previous prime is 1621640179. The next prime is 1621640257. The reversal of 1621640224 is 4220461261.

It can be written as a sum of positive squares in only one way, i.e., 1009968400 + 611671824 = 31780^2 + 24732^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1621640192 and 1621640201.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25338097 + ... + 25338160.

Almost surely, 2^1621640224 is an apocalyptic number.

It is an amenable number.

1621640224 is a deficient number, since it is larger than the sum of its proper divisors (1570964030).

1621640224 is an equidigital number, since it uses as much as digits as its factorization.

1621640224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50676267 (or 50676259 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 1621640224 is about 40269.5942865085. The cubic root of 1621640224 is about 1174.8565327173.

The spelling of 1621640224 in words is "one billion, six hundred twenty-one million, six hundred forty thousand, two hundred twenty-four".