401724 has 18 divisors (see below), whose sum is σ = 1015560. Its totient is φ = 133896.

The previous prime is 401711. The next prime is 401743. The reversal of 401724 is 427104.

Added to its reverse (427104) it gives a triangular number (828828 = T₁₂₈₇).

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×401724² = 322764344352, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 401697 and 401706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5544 + ... + 5615.

It is an arithmetic number, because the mean of its divisors is an integer number (56420).

2⁴⁰¹⁷²⁴ is an apocalyptic number.

It is an amenable number.

401724 is an abundant number, since it is smaller than the sum of its proper divisors (613836).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

401724 is a wasteful number, since it uses less digits than its factorization.

401724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11169 (or 11164 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 401724 is about 633.8170082918. The cubic root of 401724 is about 73.7863327633.

Adding to 401724 its reverse (427104), we get a palindrome (828828).

It can be divided in two parts, 40 and 1724, that added together give a square (1764 = 42²).

The spelling of 401724 in words is "four hundred one thousand, seven hundred twenty-four", and thus it is an iban number.