1620939479 has 4 divisors (see below), whose sum is σ = 1621100976. Its totient is φ = 1620777984.

The previous prime is 1620939473. The next prime is 1620939491. The reversal of 1620939479 is 9749390261.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1620939479 - 2¹² = 1620935383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620939473) 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, 64619 + ... + 86124.

It is an arithmetic number, because the mean of its divisors is an integer number (405275244).

Almost surely, 2^1620939479 is an apocalyptic number.

1620939479 is a deficient number, since it is larger than the sum of its proper divisors (161497).

1620939479 is a wasteful number, since it uses less digits than its factorization.

1620939479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161496.

The product of its (nonzero) digits is 734832, while the sum is 50.

The square root of 1620939479 is about 40260.8926751507. The cubic root of 1620939479 is about 1174.6872815599.

The spelling of 1620939479 in words is "one billion, six hundred twenty million, nine hundred thirty-nine thousand, four hundred seventy-nine".