6421156 has 27 divisors (see below), whose sum is σ = 13144257. Its totient is φ = 2736720.

The previous prime is 6421141. The next prime is 6421157. The reversal of 6421156 is 6511246.

The square root of 6421156 is 2534.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 70756 + 6350400 = 266^2 + 2520^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 6421156.

It is not an unprimeable number, because it can be changed into a prime (6421157) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 35386 + ... + 35566.

Almost surely, 2^6421156 is an apocalyptic number.

6421156 is the 2534-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6421156

6421156 is an abundant number, since it is smaller than the sum of its proper divisors (6723101).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6421156 is a wasteful number, since it uses less digits than its factorization.

6421156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380 (or 190 counting only the distinct ones).

The product of its digits is 1440, while the sum is 25.

The cubic root of 6421156 is about 185.8679063660.

Multiplying 6421156 by its sum of digits (25), we get a square (160528900 = 12670²).

The spelling of 6421156 in words is "six million, four hundred twenty-one thousand, one hundred fifty-six".