401431821 has 16 divisors (see below), whose sum is σ = 613876224. Its totient is φ = 228575664.

The previous prime is 401431819. The next prime is 401431831. The reversal of 401431821 is 128134104.

It is not a de Polignac number, because 401431821 - 2¹ = 401431819 is a prime.

It is a super-2 number, since 2×401431821² = 322295013822752082, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 401431791 and 401431800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401431831) 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, 27831 + ... + 39716.

It is an arithmetic number, because the mean of its divisors is an integer number (38367264).

Almost surely, 2^401431821 is an apocalyptic number.

It is an amenable number.

401431821 is a deficient number, since it is larger than the sum of its proper divisors (212444403).

401431821 is a wasteful number, since it uses less digits than its factorization.

401431821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67840.

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 401431821 is about 20035.7635492137. The cubic root of 401431821 is about 737.6843984373.

Adding to 401431821 its reverse (128134104), we get a palindrome (529565925).

The spelling of 401431821 in words is "four hundred one million, four hundred thirty-one thousand, eight hundred twenty-one".