1621906984 has 16 divisors (see below), whose sum is σ = 3077716320. Its totient is φ = 801182640.

The previous prime is 1621906961. The next prime is 1621907003. The reversal of 1621906984 is 4896091261.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1220652 + ... + 1221979.

It is an arithmetic number, because the mean of its divisors is an integer number (192357270).

Almost surely, 2^1621906984 is an apocalyptic number.

It is an amenable number.

1621906984 is a deficient number, since it is larger than the sum of its proper divisors (1455809336).

1621906984 is a wasteful number, since it uses less digits than its factorization.

1621906984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2442720 (or 2442716 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 46.

The square root of 1621906984 is about 40272.9063267105. The cubic root of 1621906984 is about 1174.9209505293.

The spelling of 1621906984 in words is "one billion, six hundred twenty-one million, nine hundred six thousand, nine hundred eighty-four".