1018311921 has 27 divisors (see below), whose sum is σ = 1618442553. Its totient is φ = 616520520.

The previous prime is 1018311911. The next prime is 1018311937. The reversal of 1018311921 is 1291138101.

The square root of 1018311921 is 31911.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 1018311921 - 2⁹ = 1018311409 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1018311911) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1052580 + ... + 1053546.

Almost surely, 2^1018311921 is an apocalyptic number.

1018311921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1018311921 is the 31911-st square number.

1018311921 is the 15956-th centered octagonal number.

It is an amenable number.

1018311921 is a deficient number, since it is larger than the sum of its proper divisors (600130632).

1018311921 is an frugal number, since it uses more digits than its factorization.

1018311921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1962 (or 981 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 27.

The cubic root of 1018311921 is about 1006.0670896475.

The spelling of 1018311921 in words is "one billion, eighteen million, three hundred eleven thousand, nine hundred twenty-one".