18129420 has 180 divisors, whose sum is σ = 61959744. Its totient is φ = 4432320.

The previous prime is 18129413. The next prime is 18129427. The reversal of 18129420 is 2492181.

It is an interprime number because it is at equal distance from previous prime (18129413) and next prime (18129427).

It is a tau number, because it is divible by the number of its divisors (180).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (18129427) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 584805 + ... + 584835.

Almost surely, 2^18129420 is an apocalyptic number.

18129420 is a gapful number since it is divisible by the number (10) 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 18129420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30979872).

18129420 is an abundant number, since it is smaller than the sum of its proper divisors (43830324).

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

18129420 is a wasteful number, since it uses less digits than its factorization.

18129420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 18129420 is about 4257.8656625121. The cubic root of 18129420 is about 262.7007444027.

The spelling of 18129420 in words is "eighteen million, one hundred twenty-nine thousand, four hundred twenty".