20487618 has 96 divisors (see below), whose sum is σ = 50948352. Its totient is φ = 5913600.

The previous prime is 20487617. The next prime is 20487619. The reversal of 20487618 is 81678402.

It is an interprime number because it is at equal distance from previous prime (20487617) and next prime (20487619).

It is not an unprimeable number, because it can be changed into a prime (20487613) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 288523 + ... + 288593.

It is an arithmetic number, because the mean of its divisors is an integer number (530712).

Almost surely, 2^20487618 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20487618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25474176).

20487618 is an abundant number, since it is smaller than the sum of its proper divisors (30460734).

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

20487618 is a wasteful number, since it uses less digits than its factorization.

20487618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 20487618 is about 4526.3249993786. The cubic root of 20487618 is about 273.6300706920.

The spelling of 20487618 in words is "twenty million, four hundred eighty-seven thousand, six hundred eighteen".