1620400319 has 4 divisors (see below), whose sum is σ = 1659922320. Its totient is φ = 1580878320.

The previous prime is 1620400273. The next prime is 1620400321. The reversal of 1620400319 is 9130040261.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9130040261 = 1709 ⋅5342329.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1620400319 is a prime.

It is a super-2 number, since 2×1620400319² = 5251394387630603522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620400819) 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, 19760939 + ... + 19761020.

It is an arithmetic number, because the mean of its divisors is an integer number (414980580).

Almost surely, 2^1620400319 is an apocalyptic number.

1620400319 is a deficient number, since it is larger than the sum of its proper divisors (39522001).

1620400319 is an equidigital number, since it uses as much as digits as its factorization.

1620400319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39522000.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 1620400319 is about 40254.1962905732. The cubic root of 1620400319 is about 1174.5570248708.

The spelling of 1620400319 in words is "one billion, six hundred twenty million, four hundred thousand, three hundred nineteen".