402521 has 4 divisors (see below), whose sum is σ = 460032. Its totient is φ = 345012.

The previous prime is 402517. The next prime is 402527. The reversal of 402521 is 125204.

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 402521 - 2² = 402517 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 402496 and 402505.

It is not an unprimeable number, because it can be changed into a prime (402527) 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, 28745 + ... + 28758.

It is an arithmetic number, because the mean of its divisors is an integer number (115008).

2⁴⁰²⁵²¹ is an apocalyptic number.

It is an amenable number.

402521 is a deficient number, since it is larger than the sum of its proper divisors (57511).

402521 is an equidigital number, since it uses as much as digits as its factorization.

402521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57510.

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 402521 is about 634.4454271251. The cubic root of 402521 is about 73.8350966406.

Adding to 402521 its reverse (125204), we get a palindrome (527725).

The spelling of 402521 in words is "four hundred two thousand, five hundred twenty-one".