6156421 has 4 divisors (see below), whose sum is σ = 6197344. Its totient is φ = 6115500.

The previous prime is 6156407. The next prime is 6156443. The reversal of 6156421 is 1246516.

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.

It is not a de Polignac number, because 6156421 - 2¹⁵ = 6123653 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 (6156221) 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, 20235 + ... + 20536.

It is an arithmetic number, because the mean of its divisors is an integer number (1549336).

Almost surely, 2^6156421 is an apocalyptic number.

It is an amenable number.

6156421 is a deficient number, since it is larger than the sum of its proper divisors (40923).

6156421 is a wasteful number, since it uses less digits than its factorization.

6156421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40922.

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

The square root of 6156421 is about 2481.2136143428. The cubic root of 6156421 is about 183.2776201693.

The spelling of 6156421 in words is "six million, one hundred fifty-six thousand, four hundred twenty-one".