1621345145 has 32 divisors (see below), whose sum is σ = 2363412480. Its totient is φ = 1042994880.

The previous prime is 1621345109. The next prime is 1621345147. The reversal of 1621345145 is 5415431261.

It is not a de Polignac number, because 1621345145 - 2¹² = 1621341049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1621345147) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 56660 + ... + 80330.

It is an arithmetic number, because the mean of its divisors is an integer number (73856640).

Almost surely, 2^1621345145 is an apocalyptic number.

It is an amenable number.

1621345145 is a deficient number, since it is larger than the sum of its proper divisors (742067335).

1621345145 is a wasteful number, since it uses less digits than its factorization.

1621345145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23805.

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

The square root of 1621345145 is about 40265.9303257729. The cubic root of 1621345145 is about 1174.7852681389.

The spelling of 1621345145 in words is "one billion, six hundred twenty-one million, three hundred forty-five thousand, one hundred forty-five".