621002405 has 4 divisors (see below), whose sum is σ = 745202892. Its totient is φ = 496801920.

The previous prime is 621002383. The next prime is 621002407. The reversal of 621002405 is 504200126.

It is a happy number.

621002405 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 504200126 = 2 ⋅252100063.

It can be written as a sum of positive squares in 2 ways, for example, as 315382081 + 305620324 = 17759^2 + 17482^2 .

It is not a de Polignac number, because 621002405 - 2¹⁴ = 620986021 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 (621002407) 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, 62100236 + ... + 62100245.

It is an arithmetic number, because the mean of its divisors is an integer number (186300723).

Almost surely, 2^621002405 is an apocalyptic number.

It is an amenable number.

621002405 is a deficient number, since it is larger than the sum of its proper divisors (124200487).

621002405 is a wasteful number, since it uses less digits than its factorization.

621002405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124200486.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 621002405 is about 24919.9198433703. The cubic root of 621002405 is about 853.1611953228.

The spelling of 621002405 in words is "six hundred twenty-one million, two thousand, four hundred five".