22121001 has 36 divisors (see below), whose sum is σ = 37607232. Its totient is φ = 12492144.

The previous prime is 22120957. The next prime is 22121003. The reversal of 22121001 is 10012122.

It is not a de Polignac number, because 22121001 - 2⁶ = 22120937 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22121003) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 45180 + ... + 45666.

Almost surely, 2^22121001 is an apocalyptic number.

22121001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

22121001 is a deficient number, since it is larger than the sum of its proper divisors (15486231).

22121001 is a wasteful number, since it uses less digits than its factorization.

22121001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 610 (or 600 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 22121001 is about 4703.2968224427. The cubic root of 22121001 is about 280.7167055768.

Adding to 22121001 its reverse (10012122), we get a palindrome (32133123).

The spelling of 22121001 in words is "twenty-two million, one hundred twenty-one thousand, one".