766421 has 2 divisors, whose sum is σ = 766422. Its totient is φ = 766420.

The previous prime is 766399. The next prime is 766439. The reversal of 766421 is 124667.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 703921 + 62500 = 839^2 + 250^2 .

It is a cyclic number.

It is not a de Polignac number, because 766421 - 2⁶ = 766357 is a prime.

It is a super-2 number, since 2×766421² = 1174802298482, which contains 22 as substring.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (766471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 383210 + 383211.

It is an arithmetic number, because the mean of its divisors is an integer number (383211).

2⁷⁶⁶⁴²¹ is an apocalyptic number.

It is an amenable number.

766421 is a deficient number, since it is larger than the sum of its proper divisors (1).

766421 is an equidigital number, since it uses as much as digits as its factorization.

766421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 26.

The square root of 766421 is about 875.4547389785. The cubic root of 766421 is about 91.5143357952.

The spelling of 766421 in words is "seven hundred sixty-six thousand, four hundred twenty-one".