21953052 has 96 divisors (see below), whose sum is σ = 65802240. Its totient is φ = 6255360.

The previous prime is 21953051. The next prime is 21953143. The reversal of 21953052 is 25035912.

It is a super-2 number, since 2×21953052² = 963872984229408, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21953051) 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, 19653 + ... + 20739.

It is an arithmetic number, because the mean of its divisors is an integer number (685440).

Almost surely, 2^21953052 is an apocalyptic number.

21953052 is a gapful number since it is divisible by the number (22) 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 21953052, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32901120).

21953052 is an abundant number, since it is smaller than the sum of its proper divisors (43849188).

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

21953052 is a wasteful number, since it uses less digits than its factorization.

21953052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1128 (or 1120 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 21953052 is about 4685.4084133616. The cubic root of 21953052 is about 280.0044727177.

Adding to 21953052 its reverse (25035912), we get a palindrome (46988964).

The spelling of 21953052 in words is "twenty-one million, nine hundred fifty-three thousand, fifty-two".