1620145042 has 4 divisors (see below), whose sum is σ = 2430217566. Its totient is φ = 810072520.

The previous prime is 1620145027. The next prime is 1620145049. The reversal of 1620145042 is 2405410261.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 1209717961 + 410427081 = 34781^2 + 20259^2 .

It is a super-5 number, since 5×1620145042⁵ (a number of 47 digits) contains 55555 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1620144998 and 1620145016.

It is not an unprimeable number, because it can be changed into a prime (1620145049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405036259 + ... + 405036262.

Almost surely, 2^1620145042 is an apocalyptic number.

1620145042 is a deficient number, since it is larger than the sum of its proper divisors (810072524).

1620145042 is an equidigital number, since it uses as much as digits as its factorization.

1620145042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810072523.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 1620145042 is about 40251.0253533994. The cubic root of 1620145042 is about 1174.4953419363.

The spelling of 1620145042 in words is "one billion, six hundred twenty million, one hundred forty-five thousand, forty-two".