1620515023 has 4 divisors (see below), whose sum is σ = 1620651600. Its totient is φ = 1620378448.

The previous prime is 1620515009. The next prime is 1620515053. The reversal of 1620515023 is 3205150261.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1620515023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620515053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48598 + ... + 74851.

It is an arithmetic number, because the mean of its divisors is an integer number (405162900).

Almost surely, 2^1620515023 is an apocalyptic number.

1620515023 is a deficient number, since it is larger than the sum of its proper divisors (136577).

1620515023 is a wasteful number, since it uses less digits than its factorization.

1620515023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136576.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 1620515023 is about 40255.6210112327. The cubic root of 1620515023 is about 1174.5847388475.

Adding to 1620515023 its reverse (3205150261), we get a palindrome (4825665284).

The spelling of 1620515023 in words is "one billion, six hundred twenty million, five hundred fifteen thousand, twenty-three".