102121211021 has 4 divisors (see below), whose sum is σ = 102121873344. Its totient is φ = 102120548700.

The previous prime is 102121210979. The next prime is 102121211033. The reversal of 102121211021 is 120112121201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 120112121201 = 467 ⋅257199403.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-102121211021 is a prime.

It is a super-2 number, since 2×102121211021² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102121210987 and 102121211005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102121211041) 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, 35276 + ... + 453306.

It is an arithmetic number, because the mean of its divisors is an integer number (25530468336).

Almost surely, 2^102121211021 is an apocalyptic number.

It is an amenable number.

102121211021 is a deficient number, since it is larger than the sum of its proper divisors (662323).

102121211021 is an equidigital number, since it uses as much as digits as its factorization.

102121211021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662322.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 102121211021 its reverse (120112121201), we get a palindrome (222233332222).

The spelling of 102121211021 in words is "one hundred two billion, one hundred twenty-one million, two hundred eleven thousand, twenty-one".