1621563145 has 16 divisors (see below), whose sum is σ = 1985024448. Its totient is φ = 1271350080.

The previous prime is 1621563131. The next prime is 1621563157. The reversal of 1621563145 is 5413651261.

It is not a de Polignac number, because 1621563145 - 2⁷ = 1621563017 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1621563145.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53710 + ... + 78280.

It is an arithmetic number, because the mean of its divisors is an integer number (124064028).

Almost surely, 2^1621563145 is an apocalyptic number.

It is an amenable number.

1621563145 is a deficient number, since it is larger than the sum of its proper divisors (363461303).

1621563145 is a wasteful number, since it uses less digits than its factorization.

1621563145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24840.

The product of its digits is 21600, while the sum is 34.

The square root of 1621563145 is about 40268.6372379300. The cubic root of 1621563145 is about 1174.8379181894.

The spelling of 1621563145 in words is "one billion, six hundred twenty-one million, five hundred sixty-three thousand, one hundred forty-five".