621451009 has 4 divisors (see below), whose sum is σ = 623144704. Its totient is φ = 619757316.

The previous prime is 621450983. The next prime is 621451057. The reversal of 621451009 is 900154126.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 621451009 - 2¹³ = 621442817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (621451109) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 846297 + ... + 847030.

It is an arithmetic number, because the mean of its divisors is an integer number (155786176).

Almost surely, 2^621451009 is an apocalyptic number.

It is an amenable number.

621451009 is a deficient number, since it is larger than the sum of its proper divisors (1693695).

621451009 is a wasteful number, since it uses less digits than its factorization.

621451009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1693694.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 621451009 is about 24928.9191301990. The cubic root of 621451009 is about 853.3665833636.

The spelling of 621451009 in words is "six hundred twenty-one million, four hundred fifty-one thousand, nine".