21005160 has 64 divisors (see below), whose sum is σ = 68748480. Its totient is φ = 5091840.

The previous prime is 21005143. The next prime is 21005177. The reversal of 21005160 is 6150012.

It is an interprime number because it is at equal distance from previous prime (21005143) and next prime (21005177).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6637 + ... + 9276.

It is an arithmetic number, because the mean of its divisors is an integer number (1074195).

Almost surely, 2^21005160 is an apocalyptic number.

21005160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21005160 is an abundant number, since it is smaller than the sum of its proper divisors (47743320).

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

21005160 is a wasteful number, since it uses less digits than its factorization.

21005160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15938 (or 15934 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 21005160 is about 4583.1386625325. The cubic root of 21005160 is about 275.9150126903.

Adding to 21005160 its reverse (6150012), we get a palindrome (27155172).

It can be divided in two parts, 2100 and 5160, that added together give a triangular number (7260 = T₁₂₀).

The spelling of 21005160 in words is "twenty-one million, five thousand, one hundred sixty".