402212421 has 12 divisors (see below), whose sum is σ = 625663948. Its totient is φ = 247515264.

The previous prime is 402212359. The next prime is 402212483. The reversal of 402212421 is 124212204.

402212421 is a `hidden beast` number, since 402 + 21 + 242 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (402212359) and next prime (402212483).

It can be written as a sum of positive squares in 2 ways, for example, as 37822500 + 364389921 = 6150^2 + 19089^2 .

It is not a de Polignac number, because 402212421 - 2¹⁴ = 402196037 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 402212394 and 402212403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402212021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1718740 + ... + 1718973.

Almost surely, 2^402212421 is an apocalyptic number.

It is an amenable number.

402212421 is a deficient number, since it is larger than the sum of its proper divisors (223451527).

402212421 is a wasteful number, since it uses less digits than its factorization.

402212421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3437732 (or 3437729 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 402212421 is about 20055.2342544284. The cubic root of 402212421 is about 738.1622409736.

Adding to 402212421 its reverse (124212204), we get a palindrome (526424625).

The spelling of 402212421 in words is "four hundred two million, two hundred twelve thousand, four hundred twenty-one".