91002002020 has 24 divisors (see below), whose sum is σ = 191124763200. Its totient is φ = 36396884832.

The previous prime is 91002001973. The next prime is 91002002041. The reversal of 91002002020 is 2020020019.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 91002001985 and 91002002003.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50430 + ... + 429589.

It is an arithmetic number, because the mean of its divisors is an integer number (7963531800).

Almost surely, 2^91002002020 is an apocalyptic number.

It is an amenable number.

91002002020 is an abundant number, since it is smaller than the sum of its proper divisors (100122761180).

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

91002002020 is a wasteful number, since it uses less digits than its factorization.

91002002020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 489507 (or 489505 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 91002002020 its reverse (2020020019), we get a palindrome (93022022039).

The spelling of 91002002020 in words is "ninety-one billion, two million, two thousand, twenty".