621853969 has 9 divisors (see below), whose sum is σ = 683827081. Its totient is φ = 565072420.

The previous prime is 621853957. The next prime is 621853979. The reversal of 621853969 is 969358126.

The square root of 621853969 is 24937.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 621853969 - 2¹⁵ = 621821201 is a prime.

It is a super-2 number, since 2×621853969² = 773404717522105922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (621853919) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 273174 + ... + 275440.

Almost surely, 2^621853969 is an apocalyptic number.

621853969 is the 24937-th square number.

621853969 is the 12469-th centered octagonal number.

It is an amenable number.

621853969 is a deficient number, since it is larger than the sum of its proper divisors (61973112).

621853969 is an frugal number, since it uses more digits than its factorization.

621853969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4556 (or 2278 counting only the distinct ones).

The product of its digits is 699840, while the sum is 49.

The cubic root of 621853969 is about 853.5509895870.

Multiplying 621853969 by its sum of digits (49), we get a square (30470844481 = 174559²).

The spelling of 621853969 in words is "six hundred twenty-one million, eight hundred fifty-three thousand, nine hundred sixty-nine".