21061360 has 20 divisors (see below), whose sum is σ = 48967848. Its totient is φ = 8424512.

The previous prime is 21061349. The next prime is 21061361. The reversal of 21061360 is 6316012.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21061361) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131554 + ... + 131713.

Almost surely, 2^21061360 is an apocalyptic number.

21061360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21061360 is an abundant number, since it is smaller than the sum of its proper divisors (27906488).

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

21061360 is a wasteful number, since it uses less digits than its factorization.

21061360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263280 (or 263274 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 21061360 is about 4589.2657364768. The cubic root of 21061360 is about 276.1608668030.

Adding to 21061360 its reverse (6316012), we get a palindrome (27377372).

The spelling of 21061360 in words is "twenty-one million, sixty-one thousand, three hundred sixty".