1620400313 has 16 divisors (see below), whose sum is σ = 1950768000. Its totient is φ = 1314859392.

The previous prime is 1620400273. The next prime is 1620400321. The reversal of 1620400313 is 3130040261.

It is not a de Polignac number, because 1620400313 - 2²⁶ = 1553291449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1620400813) 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, 223733 + ... + 230861.

It is an arithmetic number, because the mean of its divisors is an integer number (121923000).

Almost surely, 2^1620400313 is an apocalyptic number.

It is an amenable number.

1620400313 is a deficient number, since it is larger than the sum of its proper divisors (330367687).

1620400313 is a wasteful number, since it uses less digits than its factorization.

1620400313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8864.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 1620400313 is about 40254.1962160468. The cubic root of 1620400313 is about 1174.5570234211.

Adding to 1620400313 its reverse (3130040261), we get a palindrome (4750440574).

The spelling of 1620400313 in words is "one billion, six hundred twenty million, four hundred thousand, three hundred thirteen".