1521121420 has 96 divisors (see below), whose sum is σ = 3940126848. Its totient is φ = 480356352.

The previous prime is 1521121411. The next prime is 1521121439. The reversal of 1521121420 is 241211251.

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, 1595664 + ... + 1596616.

It is an arithmetic number, because the mean of its divisors is an integer number (41042988).

Almost surely, 2^1521121420 is an apocalyptic number.

1521121420 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 1521121420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1970063424).

1521121420 is an abundant number, since it is smaller than the sum of its proper divisors (2419005428).

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

1521121420 is a wasteful number, since it uses less digits than its factorization.

1521121420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1859 (or 1857 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 1521121420 is about 39001.5566356011. The cubic root of 1521121420 is about 1150.0621062867.

Adding to 1521121420 its reverse (241211251), we get a palindrome (1762332671).

The spelling of 1521121420 in words is "one billion, five hundred twenty-one million, one hundred twenty-one thousand, four hundred twenty".