400625 has 10 divisors (see below), whose sum is σ = 501402. Its totient is φ = 320000.

The previous prime is 400619. The next prime is 400643. The reversal of 400625 is 526004.

It can be written as a sum of positive squares in 5 ways, for example, as 73441 + 327184 = 271^2 + 572^2 .

It is not a de Polignac number, because 400625 - 2¹⁰ = 399601 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 305 + ... + 945.

2⁴⁰⁰⁶²⁵ is an apocalyptic number.

It is an amenable number.

400625 is a deficient number, since it is larger than the sum of its proper divisors (100777).

400625 is an frugal number, since it uses more digits than its factorization.

400625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 661 (or 646 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 400625 is about 632.9494450586. The cubic root of 400625 is about 73.7189853311.

Adding to 400625 its reverse (526004), we get a palindrome (926629).

It can be divided in two parts, 400 and 625, that multiplied together give a square (250000 = 500²).

The spelling of 400625 in words is "four hundred thousand, six hundred twenty-five".