401211820 has 12 divisors (see below), whose sum is σ = 842544864. Its totient is φ = 160484720.

The previous prime is 401211803. The next prime is 401211821. The reversal of 401211820 is 28112104.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (401211821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10030276 + ... + 10030315.

It is an arithmetic number, because the mean of its divisors is an integer number (70212072).

Almost surely, 2^401211820 is an apocalyptic number.

It is an amenable number.

401211820 is an abundant number, since it is smaller than the sum of its proper divisors (441333044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

401211820 is a wasteful number, since it uses less digits than its factorization.

401211820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20060600 (or 20060598 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 401211820 is about 20030.2725892585. The cubic root of 401211820 is about 737.5496134391.

Adding to 401211820 its reverse (28112104), we get a palindrome (429323924).

The spelling of 401211820 in words is "four hundred one million, two hundred eleven thousand, eight hundred twenty".