620751 has 4 divisors (see below), whose sum is σ = 827672. Its totient is φ = 413832.

The previous prime is 620743. The next prime is 620759. The reversal of 620751 is 157026.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (620743) and next prime (620759).

It is not a de Polignac number, because 620751 - 2³ = 620743 is a prime.

It is a D-number.

It is a Duffinian number.

620751 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (620759) 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, 103456 + ... + 103461.

It is an arithmetic number, because the mean of its divisors is an integer number (206918).

2⁶²⁰⁷⁵¹ is an apocalyptic number.

620751 is a deficient number, since it is larger than the sum of its proper divisors (206921).

620751 is a wasteful number, since it uses less digits than its factorization.

620751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206920.

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 620751 is about 787.8775285538. The cubic root of 620751 is about 85.3046049262.

Adding to 620751 its reverse (157026), we get a palindrome (777777).

The spelling of 620751 in words is "six hundred twenty thousand, seven hundred fifty-one".