621840026 has 4 divisors (see below), whose sum is σ = 932760042. Its totient is φ = 310920012.

The previous prime is 621840001. The next prime is 621840049. The reversal of 621840026 is 620048126.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 620048126 = 2 ⋅310024063.

It can be written as a sum of positive squares in only one way, i.e., 340439401 + 281400625 = 18451^2 + 16775^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155460005 + ... + 155460008.

Almost surely, 2^621840026 is an apocalyptic number.

621840026 is a deficient number, since it is larger than the sum of its proper divisors (310920016).

621840026 is a wasteful number, since it uses less digits than its factorization.

621840026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310920015.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 621840026 is about 24936.7204339304. The cubic root of 621840026 is about 853.5446101951.

The spelling of 621840026 in words is "six hundred twenty-one million, eight hundred forty thousand, twenty-six".