621453764 has 6 divisors (see below), whose sum is σ = 1087544094. Its totient is φ = 310726880.

The previous prime is 621453761. The next prime is 621453773. The reversal of 621453764 is 467354126.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 590004100 + 31449664 = 24290^2 + 5608^2 .

It is not an unprimeable number, because it can be changed into a prime (621453761) 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 as a sum of consecutive naturals, namely, 77681717 + ... + 77681724.

It is an arithmetic number, because the mean of its divisors is an integer number (181257349).

Almost surely, 2^621453764 is an apocalyptic number.

It is an amenable number.

621453764 is a deficient number, since it is larger than the sum of its proper divisors (466090330).

621453764 is a wasteful number, since it uses less digits than its factorization.

621453764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155363445 (or 155363443 counting only the distinct ones).

The product of its digits is 120960, while the sum is 38.

The square root of 621453764 is about 24928.9743872467. The cubic root of 621453764 is about 853.3678444023.

The spelling of 621453764 in words is "six hundred twenty-one million, four hundred fifty-three thousand, seven hundred sixty-four".