407921 has 4 divisors (see below), whose sum is σ = 409200. Its totient is φ = 406644.

The previous prime is 407917. The next prime is 407923. The reversal of 407921 is 129704.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 407921 - 2² = 407917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (407923) 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, 290 + ... + 948.

It is an arithmetic number, because the mean of its divisors is an integer number (102300).

2⁴⁰⁷⁹²¹ is an apocalyptic number.

It is an amenable number.

407921 is a deficient number, since it is larger than the sum of its proper divisors (1279).

407921 is an equidigital number, since it uses as much as digits as its factorization.

407921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1278.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 407921 is about 638.6869342644. The cubic root of 407921 is about 74.1638080510.

The spelling of 407921 in words is "four hundred seven thousand, nine hundred twenty-one".