6351661 has 4 divisors (see below), whose sum is σ = 6368800. Its totient is φ = 6334524.

The previous prime is 6351649. The next prime is 6351671. The reversal of 6351661 is 1661536.

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 a cyclic number.

It is not a de Polignac number, because 6351661 - 2⁵ = 6351629 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 (6351601) 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, 8001 + ... + 8758.

It is an arithmetic number, because the mean of its divisors is an integer number (1592200).

Almost surely, 2^6351661 is an apocalyptic number.

It is an amenable number.

6351661 is a deficient number, since it is larger than the sum of its proper divisors (17139).

6351661 is a wasteful number, since it uses less digits than its factorization.

6351661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17138.

The product of its digits is 3240, while the sum is 28.

The square root of 6351661 is about 2520.2501859934. The cubic root of 6351661 is about 185.1949345302.

The spelling of 6351661 in words is "six million, three hundred fifty-one thousand, six hundred sixty-one".