1620642053 has 4 divisors (see below), whose sum is σ = 1621834188. Its totient is φ = 1619449920.

The previous prime is 1620642043. The next prime is 1620642071. The reversal of 1620642053 is 3502460261.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3502460261 = 1867 ⋅1875983.

It can be written as a sum of positive squares in 2 ways, for example, as 561595204 + 1059046849 = 23698^2 + 32543^2 .

It is a cyclic number.

It is not a de Polignac number, because 1620642053 - 2⁸ = 1620641797 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 (1620642043) 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, 594026 + ... + 596747.

It is an arithmetic number, because the mean of its divisors is an integer number (405458547).

Almost surely, 2^1620642053 is an apocalyptic number.

It is an amenable number.

1620642053 is a deficient number, since it is larger than the sum of its proper divisors (1192135).

1620642053 is a wasteful number, since it uses less digits than its factorization.

1620642053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1192134.

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 1620642053 is about 40257.1987723935. The cubic root of 1620642053 is about 1174.6154294199.

The spelling of 1620642053 in words is "one billion, six hundred twenty million, six hundred forty-two thousand, fifty-three".