21550534 has 8 divisors (see below), whose sum is σ = 33013728. Its totient is φ = 10545960.

The previous prime is 21550519. The next prime is 21550537. The reversal of 21550534 is 43505512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21550499 and 21550508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21550537) 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, 114537 + ... + 114724.

It is an arithmetic number, because the mean of its divisors is an integer number (4126716).

Almost surely, 2^21550534 is an apocalyptic number.

21550534 is a deficient number, since it is larger than the sum of its proper divisors (11463194).

21550534 is a wasteful number, since it uses less digits than its factorization.

21550534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229310.

The product of its (nonzero) digits is 3000, while the sum is 25.

The square root of 21550534 is about 4642.2552708786. The cubic root of 21550534 is about 278.2825741597.

The spelling of 21550534 in words is "twenty-one million, five hundred fifty thousand, five hundred thirty-four".