1020009990 has 32 divisors (see below), whose sum is σ = 2463054336. Its totient is φ = 270332640.

The previous prime is 1020009967. The next prime is 1020009997. The reversal of 1020009990 is 999000201.

It is a Harshad number since it is a multiple of its sum of digits (30).

1020009990 is a modest number, since divided by 9990 gives 1020 as remainder.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020009997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 99406 + ... + 109185.

It is an arithmetic number, because the mean of its divisors is an integer number (76970448).

Almost surely, 2^1020009990 is an apocalyptic number.

1020009990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1020009990 is an abundant number, since it is smaller than the sum of its proper divisors (1443044346).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1020009990 is a wasteful number, since it uses less digits than its factorization.

1020009990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208764.

The product of its (nonzero) digits is 1458, while the sum is 30.

The square root of 1020009990 is about 31937.5952444764. The cubic root of 1020009990 is about 1006.6259958765.

The spelling of 1020009990 in words is "one billion, twenty million, nine thousand, nine hundred ninety".