1520242221 has 16 divisors (see below), whose sum is σ = 2147136768. Its totient is φ = 953472000.

The previous prime is 1520242189. The next prime is 1520242237. The reversal of 1520242221 is 1222420251.

It is not a de Polignac number, because 1520242221 - 2⁵ = 1520242189 is a prime.

It is a super-2 number, since 2×1520242221² = 4622272821022025682, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1520242621) 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, 154396 + ... + 163946.

It is an arithmetic number, because the mean of its divisors is an integer number (134196048).

Almost surely, 2^1520242221 is an apocalyptic number.

It is an amenable number.

1520242221 is a deficient number, since it is larger than the sum of its proper divisors (626894547).

1520242221 is a wasteful number, since it uses less digits than its factorization.

1520242221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12692.

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 1520242221 is about 38990.2836742694. The cubic root of 1520242221 is about 1149.8404872643.

Adding to 1520242221 its reverse (1222420251), we get a palindrome (2742662472).

The spelling of 1520242221 in words is "one billion, five hundred twenty million, two hundred forty-two thousand, two hundred twenty-one".