1521343644 has 12 divisors (see below), whose sum is σ = 3549801864. Its totient is φ = 507114544.

The previous prime is 1521343643. The next prime is 1521343669. The reversal of 1521343644 is 4463431251.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1521343643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63389307 + ... + 63389330.

It is an arithmetic number, because the mean of its divisors is an integer number (295816822).

Almost surely, 2^1521343644 is an apocalyptic number.

It is an amenable number.

1521343644 is an abundant number, since it is smaller than the sum of its proper divisors (2028458220).

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

1521343644 is a wasteful number, since it uses less digits than its factorization.

1521343644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126778644 (or 126778642 counting only the distinct ones).

The product of its digits is 34560, while the sum is 33.

The square root of 1521343644 is about 39004.4054434880. The cubic root of 1521343644 is about 1150.1181086004.

Adding to 1521343644 its reverse (4463431251), we get a palindrome (5984774895).

The spelling of 1521343644 in words is "one billion, five hundred twenty-one million, three hundred forty-three thousand, six hundred forty-four".