402121400 has 96 divisors (see below), whose sum is σ = 1000583280. Its totient is φ = 149760000.

The previous prime is 402121393. The next prime is 402121409. The reversal of 402121400 is 4121204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402121409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 342815 + ... + 343985.

Almost surely, 2^402121400 is an apocalyptic number.

402121400 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 402121400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (500291640).

402121400 is an abundant number, since it is smaller than the sum of its proper divisors (598461880).

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

402121400 is a wasteful number, since it uses less digits than its factorization.

402121400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1305 (or 1296 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 402121400 is about 20052.9648680688. The cubic root of 402121400 is about 738.1065545331.

Adding to 402121400 its reverse (4121204), we get a palindrome (406242604).

The spelling of 402121400 in words is "four hundred two million, one hundred twenty-one thousand, four hundred".