1021981153 has 8 divisors (see below), whose sum is σ = 1031711400. Its totient is φ = 1012263168.

The previous prime is 1021981099. The next prime is 1021981159. The reversal of 1021981153 is 3511891201.

It can be written as a sum of positive squares in 4 ways, for example, as 9659664 + 1012321489 = 3108^2 + 31817^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1021981153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1021981159) 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, 327163 + ... + 330271.

It is an arithmetic number, because the mean of its divisors is an integer number (128963925).

Almost surely, 2^1021981153 is an apocalyptic number.

It is an amenable number.

1021981153 is a deficient number, since it is larger than the sum of its proper divisors (9730247).

1021981153 is a wasteful number, since it uses less digits than its factorization.

1021981153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6131.

The product of its (nonzero) digits is 2160, while the sum is 31.

The square root of 1021981153 is about 31968.4399525532. The cubic root of 1021981153 is about 1007.2740114649.

The spelling of 1021981153 in words is "one billion, twenty-one million, nine hundred eighty-one thousand, one hundred fifty-three".