900201981 has 48 divisors (see below), whose sum is σ = 1430654400. Its totient is φ = 501887232.

The previous prime is 900201959. The next prime is 900201983. The reversal of 900201981 is 189102009.

It is not a de Polignac number, because 900201981 - 2¹⁰ = 900200957 is a prime.

It is a super-2 number, since 2×900201981² = 1620727213192648722, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (900201983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1085475 + ... + 1086303.

It is an arithmetic number, because the mean of its divisors is an integer number (29805300).

Almost surely, 2^900201981 is an apocalyptic number.

It is an amenable number.

900201981 is a deficient number, since it is larger than the sum of its proper divisors (530452419).

900201981 is a wasteful number, since it uses less digits than its factorization.

900201981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018 (or 1011 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 900201981 is about 30003.3661611493. The cubic root of 900201981 is about 965.5616053186.

The spelling of 900201981 in words is "nine hundred million, two hundred one thousand, nine hundred eighty-one".