21387102 has 64 divisors (see below), whose sum is σ = 49614336. Its totient is φ = 6082560.

The previous prime is 21387101. The next prime is 21387109. The reversal of 21387102 is 20178312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21387101) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 110718 + ... + 110910.

It is an arithmetic number, because the mean of its divisors is an integer number (775224).

Almost surely, 2^21387102 is an apocalyptic number.

21387102 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21387102, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24807168).

21387102 is an abundant number, since it is smaller than the sum of its proper divisors (28227234).

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

21387102 is a wasteful number, since it uses less digits than its factorization.

21387102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305.

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 21387102 is about 4624.6191194519. The cubic root of 21387102 is about 277.5773212018.

The spelling of 21387102 in words is "twenty-one million, three hundred eighty-seven thousand, one hundred two".