21121350 has 48 divisors (see below), whose sum is σ = 55145280. Its totient is φ = 5335200.

The previous prime is 21121349. The next prime is 21121363. The reversal of 21121350 is 5312112.

It is a super-2 number, since 2×21121350² = 892222851645000, which contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 856 + ... + 6555.

It is an arithmetic number, because the mean of its divisors is an integer number (1148860).

Almost surely, 2^21121350 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21121350, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27572640).

21121350 is an abundant number, since it is smaller than the sum of its proper divisors (34023930).

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

21121350 is a wasteful number, since it uses less digits than its factorization.

21121350 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7445 (or 7440 counting only the distinct ones).

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

The square root of 21121350 is about 4595.7969929056. The cubic root of 21121350 is about 276.4228186402.

Adding to 21121350 its reverse (5312112), we get a palindrome (26433462).

The spelling of 21121350 in words is "twenty-one million, one hundred twenty-one thousand, three hundred fifty".