642062021 has 4 divisors (see below), whose sum is σ = 649797792. Its totient is φ = 634326252.

The previous prime is 642062011. The next prime is 642062039. The reversal of 642062021 is 120260246.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 120260246 = 2 ⋅60130123.

It is a cyclic number.

It is not a de Polignac number, because 642062021 - 2⁶ = 642061957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642062011) 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 in 3 ways as a sum of consecutive naturals, for example, 3867761 + ... + 3867926.

It is an arithmetic number, because the mean of its divisors is an integer number (162449448).

Almost surely, 2^642062021 is an apocalyptic number.

It is an amenable number.

642062021 is a deficient number, since it is larger than the sum of its proper divisors (7735771).

642062021 is an equidigital number, since it uses as much as digits as its factorization.

642062021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7735770.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 642062021 is about 25338.9427758934. The cubic root of 642062021 is about 862.6984024708.

The spelling of 642062021 in words is "six hundred forty-two million, sixty-two thousand, twenty-one".