621142 has 4 divisors (see below), whose sum is σ = 931716. Its totient is φ = 310570.

The previous prime is 621139. The next prime is 621143. The reversal of 621142 is 241126.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 241126 = 2 ⋅120563.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155284 + ... + 155287.

It is an arithmetic number, because the mean of its divisors is an integer number (232929).

2⁶²¹¹⁴² is an apocalyptic number.

621142 is a deficient number, since it is larger than the sum of its proper divisors (310574).

621142 is a wasteful number, since it uses less digits than its factorization.

621142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310573.

The product of its digits is 96, while the sum is 16.

The square root of 621142 is about 788.1256245041. The cubic root of 621142 is about 85.3225117842.

Subtracting from 621142 its sum of digits (16), we obtain a palindrome (621126).

Adding to 621142 its reverse (241126), we get a palindrome (862268).

The spelling of 621142 in words is "six hundred twenty-one thousand, one hundred forty-two".