407661 has 4 divisors (see below), whose sum is σ = 543552. Its totient is φ = 271772.

The previous prime is 407657. The next prime is 407669. The reversal of 407661 is 166704.

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 407661 - 2² = 407657 is a prime.

It is a D-number.

407661 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (407669) 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, 67941 + ... + 67946.

It is an arithmetic number, because the mean of its divisors is an integer number (135888).

2⁴⁰⁷⁶⁶¹ is an apocalyptic number.

It is an amenable number.

407661 is a deficient number, since it is larger than the sum of its proper divisors (135891).

407661 is a wasteful number, since it uses less digits than its factorization.

407661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135890.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 407661 is about 638.4833592193. The cubic root of 407661 is about 74.1480479011.

The spelling of 407661 in words is "four hundred seven thousand, six hundred sixty-one".