400001243 has 8 divisors (see below), whose sum is σ = 421677120. Its totient is φ = 378387720.

The previous prime is 400001233. The next prime is 400001249. The reversal of 400001243 is 342100004.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 400001243 - 2⁴ = 400001227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400001249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2105 + ... + 28362.

It is an arithmetic number, because the mean of its divisors is an integer number (52709640).

Almost surely, 2^400001243 is an apocalyptic number.

400001243 is a deficient number, since it is larger than the sum of its proper divisors (21675877).

400001243 is a wasteful number, since it uses less digits than its factorization.

400001243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31177.

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 400001243 is about 20000.0310749759. The cubic root of 400001243 is about 736.8070629358.

Adding to 400001243 its reverse (342100004), we get a palindrome (742101247).

The spelling of 400001243 in words is "four hundred million, one thousand, two hundred forty-three".