1028921771 has 4 divisors (see below), whose sum is σ = 1029134544. Its totient is φ = 1028709000.

The previous prime is 1028921749. The next prime is 1028921783. The reversal of 1028921771 is 1771298201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1771298201 = 12457 ⋅142193.

It is a cyclic number.

It is not a de Polignac number, because 1028921771 - 2¹⁸ = 1028659627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1028921371) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98960 + ... + 108861.

It is an arithmetic number, because the mean of its divisors is an integer number (257283636).

Almost surely, 2^1028921771 is an apocalyptic number.

1028921771 is a deficient number, since it is larger than the sum of its proper divisors (212773).

1028921771 is an equidigital number, since it uses as much as digits as its factorization.

1028921771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212772.

The product of its (nonzero) digits is 14112, while the sum is 38.

The square root of 1028921771 is about 32076.8104867052. The cubic root of 1028921771 is about 1009.5491144984.

The spelling of 1028921771 in words is "one billion, twenty-eight million, nine hundred twenty-one thousand, seven hundred seventy-one".