1620020747 has 2 divisors, whose sum is σ = 1620020748. Its totient is φ = 1620020746.

The previous prime is 1620020711. The next prime is 1620020749. The reversal of 1620020747 is 7470200261.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1620020747 - 2²⁰ = 1618972171 is a prime.

Together with 1620020749, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1620020749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810010373 + 810010374.

It is an arithmetic number, because the mean of its divisors is an integer number (810010374).

Almost surely, 2^1620020747 is an apocalyptic number.

1620020747 is a deficient number, since it is larger than the sum of its proper divisors (1).

1620020747 is an equidigital number, since it uses as much as digits as its factorization.

1620020747 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4704, while the sum is 29.

The square root of 1620020747 is about 40249.4813258506. The cubic root of 1620020747 is about 1174.4653060181.

The spelling of 1620020747 in words is "one billion, six hundred twenty million, twenty thousand, seven hundred forty-seven".