1031261621220 has 48 divisors (see below), whose sum is σ = 3208369489920. Its totient is φ = 275003098848.

The previous prime is 1031261621207. The next prime is 1031261621251. The reversal of 1031261621220 is 221261621301.

1031261621220 is a `hidden beast` number, since 1 + 0 + 3 + 1 + 2 + 616 + 21 + 2 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 954871332 + ... + 954872411.

It is an arithmetic number, because the mean of its divisors is an integer number (66841031040).

Almost surely, 2^{1031261621220} is an apocalyptic number.

1031261621220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1031261621220 is an abundant number, since it is smaller than the sum of its proper divisors (2177107868700).

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

1031261621220 is a wasteful number, since it uses less digits than its factorization.

1031261621220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1909743761 (or 1909743753 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The spelling of 1031261621220 in words is "one trillion, thirty-one billion, two hundred sixty-one million, six hundred twenty-one thousand, two hundred twenty".