400241391 has 16 divisors (see below), whose sum is σ = 584722560. Its totient is φ = 241506720.

The previous prime is 400241381. The next prime is 400241393. The reversal of 400241391 is 193142004.

It is not a de Polignac number, because 400241391 - 2¹⁹ = 399717103 is a prime.

It is a super-2 number, since 2×400241391² = 320386342139229762, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400241393) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18925 + ... + 34038.

It is an arithmetic number, because the mean of its divisors is an integer number (36545160).

Almost surely, 2^400241391 is an apocalyptic number.

400241391 is a deficient number, since it is larger than the sum of its proper divisors (184481169).

400241391 is a wasteful number, since it uses less digits than its factorization.

400241391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53206.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 400241391 is about 20006.0338648119. The cubic root of 400241391 is about 736.9544852644.

Adding to 400241391 its reverse (193142004), we get a palindrome (593383395).

The spelling of 400241391 in words is "four hundred million, two hundred forty-one thousand, three hundred ninety-one".