400001125 has 16 divisors (see below), whose sum is σ = 511383600. Its totient is φ = 312192000.

The previous prime is 400001113. The next prime is 400001137. The reversal of 400001125 is 521100004.

It is an interprime number because it is at equal distance from previous prime (400001113) and next prime (400001137).

It can be written as a sum of positive squares in 8 ways, for example, as 294774561 + 105226564 = 17169^2 + 10258^2 .

It is not a de Polignac number, because 400001125 - 2¹⁵ = 399968357 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33900 + ... + 44149.

It is an arithmetic number, because the mean of its divisors is an integer number (31961475).

Almost surely, 2^400001125 is an apocalyptic number.

It is an amenable number.

400001125 is a deficient number, since it is larger than the sum of its proper divisors (111382475).

400001125 is an equidigital number, since it uses as much as digits as its factorization.

400001125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78105 (or 78095 counting only the distinct ones).

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

The square root of 400001125 is about 20000.0281249802. The cubic root of 400001125 is about 736.8069904833.

Adding to 400001125 its reverse (521100004), we get a palindrome (921101129).

The spelling of 400001125 in words is "four hundred million, one thousand, one hundred twenty-five".