1620652221 has 24 divisors (see below), whose sum is σ = 2380641120. Its totient is φ = 1062266400.

The previous prime is 1620652183. The next prime is 1620652249. The reversal of 1620652221 is 1222560261.

1620652221 is a `hidden beast` number, since 1 + 6 + 2 + 0 + 652 + 2 + 2 + 1 = 666.

It is not a de Polignac number, because 1620652221 - 2⁶ = 1620652157 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620650221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 122206 + ... + 134816.

It is an arithmetic number, because the mean of its divisors is an integer number (99193380).

Almost surely, 2^1620652221 is an apocalyptic number.

It is an amenable number.

1620652221 is a deficient number, since it is larger than the sum of its proper divisors (759988899).

1620652221 is a wasteful number, since it uses less digits than its factorization.

1620652221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12857 (or 12854 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 1620652221 is about 40257.3250601676. The cubic root of 1620652221 is about 1174.6178859494.

The spelling of 1620652221 in words is "one billion, six hundred twenty million, six hundred fifty-two thousand, two hundred twenty-one".