1621351312 has 80 divisors (see below), whose sum is σ = 3647659392. Its totient is φ = 683827200.

The previous prime is 1621351309. The next prime is 1621351313. The reversal of 1621351312 is 2131531261.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (1621351313) 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, 2312562 + ... + 2313262.

Almost surely, 2^1621351312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1621351312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1823829696).

1621351312 is an abundant number, since it is smaller than the sum of its proper divisors (2026308080).

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

1621351312 is a wasteful number, since it uses less digits than its factorization.

1621351312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1016 (or 1010 counting only the distinct ones).

The product of its digits is 1080, while the sum is 25.

The square root of 1621351312 is about 40266.0069040872. The cubic root of 1621351312 is about 1174.7867576206.

Adding to 1621351312 its reverse (2131531261), we get a palindrome (3752882573).

The spelling of 1621351312 in words is "one billion, six hundred twenty-one million, three hundred fifty-one thousand, three hundred twelve".