7861421 has 4 divisors (see below), whose sum is σ = 8275200. Its totient is φ = 7447644.

The previous prime is 7861417. The next prime is 7861489. The reversal of 7861421 is 1241687.

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: 1241687 = 139 ⋅8933.

It is a cyclic number.

It is not a de Polignac number, because 7861421 - 2² = 7861417 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 (7861411) 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, 206861 + ... + 206898.

It is an arithmetic number, because the mean of its divisors is an integer number (2068800).

Almost surely, 2^7861421 is an apocalyptic number.

It is an amenable number.

7861421 is a deficient number, since it is larger than the sum of its proper divisors (413779).

7861421 is a wasteful number, since it uses less digits than its factorization.

7861421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413778.

The product of its digits is 2688, while the sum is 29.

The square root of 7861421 is about 2803.8225692793. The cubic root of 7861421 is about 198.8384419747.

The spelling of 7861421 in words is "seven million, eight hundred sixty-one thousand, four hundred twenty-one".