21151260 has 192 divisors, whose sum is σ = 74511360. Its totient is φ = 4942080.

The previous prime is 21151259. The next prime is 21151271. The reversal of 21151260 is 6215112.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 161395 + ... + 161525.

It is an arithmetic number, because the mean of its divisors is an integer number (388080).

Almost surely, 2^21151260 is an apocalyptic number.

21151260 is a gapful number since it is divisible by the number (20) 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 21151260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37255680).

21151260 is an abundant number, since it is smaller than the sum of its proper divisors (53360100).

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

21151260 is a wasteful number, since it uses less digits than its factorization.

21151260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 21151260 is about 4599.0499018819. The cubic root of 21151260 is about 276.5532381271.

Adding to 21151260 its reverse (6215112), we get a palindrome (27366372).

It can be divided in two parts, 2115 and 1260, that added together give a cube (3375 = 15³).

The spelling of 21151260 in words is "twenty-one million, one hundred fifty-one thousand, two hundred sixty".