102021001020 has 72 divisors (see below), whose sum is σ = 309498068880. Its totient is φ = 27202579200.

The previous prime is 102021000971. The next prime is 102021001067. The reversal of 102021001020 is 20100120201.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 102021000993 and 102021001011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1933995 + ... + 1986045.

It is an arithmetic number, because the mean of its divisors is an integer number (4298584290).

Almost surely, 2^102021001020 is an apocalyptic number.

102021001020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

102021001020 is an abundant number, since it is smaller than the sum of its proper divisors (207477067860).

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

102021001020 is a wasteful number, since it uses less digits than its factorization.

102021001020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62955 (or 62950 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 102021001020 its reverse (20100120201), we get a palindrome (122121121221).

The spelling of 102021001020 in words is "one hundred two billion, twenty-one million, one thousand, twenty".