621969983 has 4 divisors (see below), whose sum is σ = 624215640. Its totient is φ = 619724328.

The previous prime is 621969977. The next prime is 621969991. The reversal of 621969983 is 389969126.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 389969126 = 2 ⋅194984563.

It is a cyclic number.

It is not a de Polignac number, because 621969983 - 2⁶ = 621969919 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 (621969913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1122413 + ... + 1122966.

It is an arithmetic number, because the mean of its divisors is an integer number (156053910).

Almost surely, 2^621969983 is an apocalyptic number.

621969983 is a deficient number, since it is larger than the sum of its proper divisors (2245657).

621969983 is a wasteful number, since it uses less digits than its factorization.

621969983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2245656.

The product of its digits is 1259712, while the sum is 53.

The square root of 621969983 is about 24939.3260333955. The cubic root of 621969983 is about 853.6040661998.

The spelling of 621969983 in words is "six hundred twenty-one million, nine hundred sixty-nine thousand, nine hundred eighty-three".