2001021554 has 16 divisors (see below), whose sum is σ = 3444562176. Its totient is φ = 854020800.

The previous prime is 2001021541. The next prime is 2001021559. The reversal of 2001021554 is 4551201002.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2001021559) 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, 293162 + ... + 299909.

It is an arithmetic number, because the mean of its divisors is an integer number (215285136).

Almost surely, 2^2001021554 is an apocalyptic number.

2001021554 is a deficient number, since it is larger than the sum of its proper divisors (1443540622).

2001021554 is a wasteful number, since it uses less digits than its factorization.

2001021554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 593321.

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 2001021554 is about 44732.7794128646. The cubic root of 2001021554 is about 1260.1355262805.

Adding to 2001021554 its reverse (4551201002), we get a palindrome (6552222556).

The spelling of 2001021554 in words is "two billion, one million, twenty-one thousand, five hundred fifty-four".