202156981 has 8 divisors (see below), whose sum is σ = 217901880. Its totient is φ = 186439872.

The previous prime is 202156963. The next prime is 202156987. The reversal of 202156981 is 189651202.

202156981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 5904900 + 196252081 = 2430^2 + 14009^2 .

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 202156981 - 2¹³ = 202148789 is a prime.

It is a super-2 number, since 2×202156981² = 81734889934068722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202156987) 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, 9651 + ... + 22303.

It is an arithmetic number, because the mean of its divisors is an integer number (27237735).

Almost surely, 2^202156981 is an apocalyptic number.

It is an amenable number.

202156981 is a deficient number, since it is larger than the sum of its proper divisors (15744899).

202156981 is a wasteful number, since it uses less digits than its factorization.

202156981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13895.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 202156981 is about 14218.1919033329. The cubic root of 202156981 is about 586.8983849559.

The spelling of 202156981 in words is "two hundred two million, one hundred fifty-six thousand, nine hundred eighty-one".