1021867899 has 48 divisors (see below), whose sum is σ = 1561027104. Its totient is φ = 590976000.

The previous prime is 1021867883. The next prime is 1021867919. The reversal of 1021867899 is 9987681201.

It is not a de Polignac number, because 1021867899 - 2⁴ = 1021867883 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021867859) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2548099 + ... + 2548499.

It is an arithmetic number, because the mean of its divisors is an integer number (32521398).

Almost surely, 2^1021867899 is an apocalyptic number.

1021867899 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1021867899 is a deficient number, since it is larger than the sum of its proper divisors (539159205).

1021867899 is a wasteful number, since it uses less digits than its factorization.

1021867899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636 (or 617 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 51.

The square root of 1021867899 is about 31966.6685627389. The cubic root of 1021867899 is about 1007.2368020295.

The spelling of 1021867899 in words is "one billion, twenty-one million, eight hundred sixty-seven thousand, eight hundred ninety-nine".