1020621660 has 24 divisors (see below), whose sum is σ = 2857740816. Its totient is φ = 272165760.

The previous prime is 1020621659. The next prime is 1020621713. The reversal of 1020621660 is 661260201.

It is a super-2 number, since 2×1020621660² = 2083337145722311200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1020621660.

It is a congruent number.

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, 8505121 + ... + 8505240.

It is an arithmetic number, because the mean of its divisors is an integer number (119072534).

Almost surely, 2^1020621660 is an apocalyptic number.

1020621660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1020621660 is an abundant number, since it is smaller than the sum of its proper divisors (1837119156).

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

1020621660 is a wasteful number, since it uses less digits than its factorization.

1020621660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17010373 (or 17010371 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 1020621660 is about 31947.1698277015. The cubic root of 1020621660 is about 1006.8271703398.

Adding to 1020621660 its reverse (661260201), we get a palindrome (1681881861).

The spelling of 1020621660 in words is "one billion, twenty million, six hundred twenty-one thousand, six hundred sixty".