1621640552 has 16 divisors (see below), whose sum is σ = 3474944160. Its totient is φ = 694988784.

The previous prime is 1621640543. The next prime is 1621640561. The reversal of 1621640552 is 2550461261.

It is an interprime number because it is at equal distance from previous prime (1621640543) and next prime (1621640561).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14478878 + ... + 14478989.

It is an arithmetic number, because the mean of its divisors is an integer number (217184010).

Almost surely, 2^1621640552 is an apocalyptic number.

It is an amenable number.

1621640552 is an abundant number, since it is smaller than the sum of its proper divisors (1853303608).

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

1621640552 is a wasteful number, since it uses less digits than its factorization.

1621640552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28957880 (or 28957876 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 1621640552 is about 40269.5983590599. The cubic root of 1621640552 is about 1174.8566119278.

The spelling of 1621640552 in words is "one billion, six hundred twenty-one million, six hundred forty thousand, five hundred fifty-two".