1201040021 has 16 divisors (see below), whose sum is σ = 1301287680. Its totient is φ = 1104176640.

The previous prime is 1201040003. The next prime is 1201040039. The reversal of 1201040021 is 1200401021.

It is an interprime number because it is at equal distance from previous prime (1201040003) and next prime (1201040039).

It is a de Polignac number, because none of the positive numbers 2^k-1201040021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1201039984 and 1201040011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201040051) 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, 525401 + ... + 527681.

It is an arithmetic number, because the mean of its divisors is an integer number (81330480).

Almost surely, 2^1201040021 is an apocalyptic number.

It is an amenable number.

1201040021 is a deficient number, since it is larger than the sum of its proper divisors (100247659).

1201040021 is a wasteful number, since it uses less digits than its factorization.

1201040021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3004.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 1201040021 is about 34656.0243103562. The cubic root of 1201040021 is about 1062.9654769878.

Adding to 1201040021 its reverse (1200401021), we get a palindrome (2401441042).

The spelling of 1201040021 in words is "one billion, two hundred one million, forty thousand, twenty-one".