1021981629 has 4 divisors (see below), whose sum is σ = 1362642176. Its totient is φ = 681321084.

The previous prime is 1021981627. The next prime is 1021981651. The reversal of 1021981629 is 9261891201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1021981629 - 2¹ = 1021981627 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021981627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 170330269 + ... + 170330274.

It is an arithmetic number, because the mean of its divisors is an integer number (340660544).

Almost surely, 2^1021981629 is an apocalyptic number.

It is an amenable number.

1021981629 is a deficient number, since it is larger than the sum of its proper divisors (340660547).

1021981629 is an equidigital number, since it uses as much as digits as its factorization.

1021981629 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340660546.

The product of its (nonzero) digits is 15552, while the sum is 39.

The square root of 1021981629 is about 31968.4473973948. The cubic root of 1021981629 is about 1007.2741678482.

The spelling of 1021981629 in words is "one billion, twenty-one million, nine hundred eighty-one thousand, six hundred twenty-nine".