21429198 has 48 divisors (see below), whose sum is σ = 55036800. Its totient is φ = 6121656.

The previous prime is 21429193. The next prime is 21429209. The reversal of 21429198 is 89192412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21429193) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 253 + ... + 6551.

It is an arithmetic number, because the mean of its divisors is an integer number (1146600).

Almost surely, 2^21429198 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21429198, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27518400).

21429198 is an abundant number, since it is smaller than the sum of its proper divisors (33607602).

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

21429198 is an equidigital number, since it uses as much as digits as its factorization.

21429198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6323 (or 6311 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 21429198 is about 4629.1681758173. The cubic root of 21429198 is about 277.7593193186.

The spelling of 21429198 in words is "twenty-one million, four hundred twenty-nine thousand, one hundred ninety-eight".