1210021660 has 12 divisors (see below), whose sum is σ = 2541045528. Its totient is φ = 484008656.

The previous prime is 1210021639. The next prime is 1210021711. The reversal of 1210021660 is 661200121.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30250522 + ... + 30250561.

It is an arithmetic number, because the mean of its divisors is an integer number (211753794).

Almost surely, 2^1210021660 is an apocalyptic number.

1210021660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1210021660 is an abundant number, since it is smaller than the sum of its proper divisors (1331023868).

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

1210021660 is a wasteful number, since it uses less digits than its factorization.

1210021660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60501092 (or 60501090 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 1210021660 is about 34785.3656010685. The cubic root of 1210021660 is about 1065.6085951156.

Adding to 1210021660 its reverse (661200121), we get a palindrome (1871221781).

The spelling of 1210021660 in words is "one billion, two hundred ten million, twenty-one thousand, six hundred sixty".