1620217544 has 16 divisors (see below), whose sum is σ = 3314081520. Its totient is φ = 736462480.

The previous prime is 1620217513. The next prime is 1620217561. The reversal of 1620217544 is 4457120261.

It is a self number, because there is not a number n which added to its sum of digits gives 1620217544.

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, 9205694 + ... + 9205869.

It is an arithmetic number, because the mean of its divisors is an integer number (207130095).

Almost surely, 2^1620217544 is an apocalyptic number.

It is an amenable number.

1620217544 is an abundant number, since it is smaller than the sum of its proper divisors (1693863976).

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

1620217544 is a wasteful number, since it uses less digits than its factorization.

1620217544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18411580 (or 18411576 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 1620217544 is about 40251.9259663435. The cubic root of 1620217544 is about 1174.5128613536.

The spelling of 1620217544 in words is "one billion, six hundred twenty million, two hundred seventeen thousand, five hundred forty-four".