1620138019 has 4 divisors (see below), whose sum is σ = 1621211760. Its totient is φ = 1619064280.

The previous prime is 1620138007. The next prime is 1620138043. The reversal of 1620138019 is 9108310261.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9108310261 = 5953 ⋅1530037.

It is a cyclic number.

It is not a de Polignac number, because 1620138019 - 2¹³ = 1620129827 is a prime.

It is a super-2 number, since 2×1620138019² = 5249694401218488722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1620138049) by changing a digit.

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, 534604 + ... + 537625.

It is an arithmetic number, because the mean of its divisors is an integer number (405302940).

Almost surely, 2^1620138019 is an apocalyptic number.

1620138019 is a deficient number, since it is larger than the sum of its proper divisors (1073741).

1620138019 is a wasteful number, since it uses less digits than its factorization.

1620138019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1073740.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 1620138019 is about 40250.9381132912. The cubic root of 1620138019 is about 1174.4936448675.

The spelling of 1620138019 in words is "one billion, six hundred twenty million, one hundred thirty-eight thousand, nineteen".