1220831540 has 48 divisors (see below), whose sum is σ = 2760609600. Its totient is φ = 451809792.

The previous prime is 1220831509. The next prime is 1220831543. The reversal of 1220831540 is 451380221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220831543) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10370 + ... + 50489.

It is an arithmetic number, because the mean of its divisors is an integer number (57512700).

Almost surely, 2^1220831540 is an apocalyptic number.

1220831540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1220831540 is an abundant number, since it is smaller than the sum of its proper divisors (1539778060).

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

1220831540 is a wasteful number, since it uses less digits than its factorization.

1220831540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60944 (or 60942 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 1220831540 is about 34940.3998259894. The cubic root of 1220831540 is about 1068.7724414653.

The spelling of 1220831540 in words is "one billion, two hundred twenty million, eight hundred thirty-one thousand, five hundred forty".