1015221620 has 96 divisors (see below), whose sum is σ = 2501839872. Its totient is φ = 338830848.

The previous prime is 1015221619. The next prime is 1015221631. The reversal of 1015221620 is 261225101.

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 = 1015221592 and 1015221601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1822382 + ... + 1822938.

It is an arithmetic number, because the mean of its divisors is an integer number (26060832).

Almost surely, 2^1015221620 is an apocalyptic number.

1015221620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1015221620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1250919936).

1015221620 is an abundant number, since it is smaller than the sum of its proper divisors (1486618252).

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

1015221620 is a wasteful number, since it uses less digits than its factorization.

1015221620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 897 (or 895 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 1015221620 is about 31862.5425852991. The cubic root of 1015221620 is about 1005.0483446625.

Adding to 1015221620 its reverse (261225101), we get a palindrome (1276446721).

The spelling of 1015221620 in words is "one billion, fifteen million, two hundred twenty-one thousand, six hundred twenty".