1621002121 has 8 divisors (see below), whose sum is σ = 1677083904. Its totient is φ = 1565157360.

The previous prime is 1621002101. The next prime is 1621002127. The reversal of 1621002121 is 1212001261.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1621002121 - 2²⁵ = 1587447689 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1621002095 and 1621002104.

It is not an unprimeable number, because it can be changed into a prime (1621002127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45286 + ... + 72751.

It is an arithmetic number, because the mean of its divisors is an integer number (209635488).

Almost surely, 2^1621002121 is an apocalyptic number.

It is an amenable number.

1621002121 is a deficient number, since it is larger than the sum of its proper divisors (56081783).

1621002121 is a wasteful number, since it uses less digits than its factorization.

1621002121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118511.

The product of its (nonzero) digits is 48, while the sum is 16.

The square root of 1621002121 is about 40261.6706185921. The cubic root of 1621002121 is about 1174.7024134867.

Adding to 1621002121 its reverse (1212001261), we get a palindrome (2833003382).

The spelling of 1621002121 in words is "one billion, six hundred twenty-one million, two thousand, one hundred twenty-one".