402212001221 has 4 divisors (see below), whose sum is σ = 402233783244. Its totient is φ = 402190219200.

The previous prime is 402212001209. The next prime is 402212001239. The reversal of 402212001221 is 122100212204.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 298537660996 + 103674340225 = 546386^2 + 321985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-402212001221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 402212001221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402212001271) 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, 10863290 + ... + 10900251.

It is an arithmetic number, because the mean of its divisors is an integer number (100558445811).

Almost surely, 2^402212001221 is an apocalyptic number.

It is an amenable number.

402212001221 is a deficient number, since it is larger than the sum of its proper divisors (21782023).

402212001221 is a wasteful number, since it uses less digits than its factorization.

402212001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21782022.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 402212001221 its reverse (122100212204), we get a palindrome (524312213425).

The spelling of 402212001221 in words is "four hundred two billion, two hundred twelve million, one thousand, two hundred twenty-one".