1421200121 has 4 divisors (see below), whose sum is σ = 1550400144. Its totient is φ = 1292000100.

The previous prime is 1421200103. The next prime is 1421200139. The reversal of 1421200121 is 1210021241.

It is a happy number.

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.

It is an interprime number because it is at equal distance from previous prime (1421200103) and next prime (1421200139).

It is a cyclic number.

It is not a de Polignac number, because 1421200121 - 2¹⁸ = 1420937977 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1421200096 and 1421200105.

It is not an unprimeable number, because it can be changed into a prime (1421200621) 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, 64599995 + ... + 64600016.

It is an arithmetic number, because the mean of its divisors is an integer number (387600036).

Almost surely, 2^1421200121 is an apocalyptic number.

1421200121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1421200121 is a deficient number, since it is larger than the sum of its proper divisors (129200023).

1421200121 is a wasteful number, since it uses less digits than its factorization.

1421200121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129200022.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 1421200121 is about 37698.8079519764. The cubic root of 1421200121 is about 1124.3074245207.

Adding to 1421200121 its reverse (1210021241), we get a palindrome (2631221362).

The spelling of 1421200121 in words is "one billion, four hundred twenty-one million, two hundred thousand, one hundred twenty-one".