21601055 has 16 divisors (see below), whose sum is σ = 30348864. Its totient is φ = 14449920.

The previous prime is 21600991. The next prime is 21601061. The reversal of 21601055 is 55010612.

It is not a de Polignac number, because 21601055 - 2⁶ = 21600991 is a prime.

It is a super-2 number, since 2×21601055² = 933211154226050, which contains 22 as substring.

It is a congruent number.

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, 6092 + ... + 8961.

It is an arithmetic number, because the mean of its divisors is an integer number (1896804).

Almost surely, 2^21601055 is an apocalyptic number.

21601055 is a deficient number, since it is larger than the sum of its proper divisors (8747809).

21601055 is a wasteful number, since it uses less digits than its factorization.

21601055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15106.

The product of its (nonzero) digits is 300, while the sum is 20.

The square root of 21601055 is about 4647.6935139916. The cubic root of 21601055 is about 278.4998640876.

Adding to 21601055 its reverse (55010612), we get a palindrome (76611667).

The spelling of 21601055 in words is "twenty-one million, six hundred one thousand, fifty-five".