401521 has 4 divisors (see below), whose sum is σ = 410112. Its totient is φ = 392932.

The previous prime is 401519. The next prime is 401537. The reversal of 401521 is 125104.

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 401521 - 2¹ = 401519 is a prime.

It is a super-2 number, since 2×401521² = 322438226882, which contains 22 as substring.

It is a Duffinian number.

401521 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (401551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4225 + ... + 4318.

It is an arithmetic number, because the mean of its divisors is an integer number (102528).

2⁴⁰¹⁵²¹ is an apocalyptic number.

It is an amenable number.

401521 is a deficient number, since it is larger than the sum of its proper divisors (8591).

401521 is an equidigital number, since it uses as much as digits as its factorization.

401521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8590.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 401521 is about 633.6568471973. The cubic root of 401521 is about 73.7739020487.

Adding to 401521 its reverse (125104), we get a palindrome (526625).

The spelling of 401521 in words is "four hundred one thousand, five hundred twenty-one".