1213520420 has 48 divisors (see below), whose sum is σ = 3006409728. Its totient is φ = 402641280.

The previous prime is 1213520417. The next prime is 1213520431. The reversal of 1213520420 is 240253121.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1213520392 and 1213520401.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135467 + ... + 144146.

It is an arithmetic number, because the mean of its divisors is an integer number (62633536).

Almost surely, 2^1213520420 is an apocalyptic number.

1213520420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1213520420 is an abundant number, since it is smaller than the sum of its proper divisors (1792889308).

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

1213520420 is a wasteful number, since it uses less digits than its factorization.

1213520420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279660 (or 279658 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 1213520420 is about 34835.6199887414. The cubic root of 1213520420 is about 1066.6346706982.

Adding to 1213520420 its reverse (240253121), we get a palindrome (1453773541).

The spelling of 1213520420 in words is "one billion, two hundred thirteen million, five hundred twenty thousand, four hundred twenty".