21210121010 has 32 divisors (see below), whose sum is σ = 41499283392. Its totient is φ = 7758233280.

The previous prime is 21210120973. The next prime is 21210121013. The reversal of 21210121010 is 1012101212.

21210121010 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21210120982 and 21210121000.

It is not an unprimeable number, because it can be changed into a prime (21210121013) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 748496 + ... + 776315.

It is an arithmetic number, because the mean of its divisors is an integer number (1296852606).

Almost surely, 2^21210121010 is an apocalyptic number.

21210121010 is a deficient number, since it is larger than the sum of its proper divisors (20289162382).

21210121010 is a wasteful number, since it uses less digits than its factorization.

21210121010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1524938.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21210121010 its reverse (1012101212), we get a palindrome (22222222222).

The spelling of 21210121010 in words is "twenty-one billion, two hundred ten million, one hundred twenty-one thousand, ten".