623765421 has 16 divisors (see below), whose sum is σ = 972734400. Its totient is φ = 393956784.

The previous prime is 623765413. The next prime is 623765449. The reversal of 623765421 is 124567326.

623765421 is a `hidden beast` number, since 623 + 7 + 6 + 5 + 4 + 21 = 666.

It is not a de Polignac number, because 623765421 - 2³ = 623765413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (623765621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 607446 + ... + 608471.

It is an arithmetic number, because the mean of its divisors is an integer number (60795900).

Almost surely, 2^623765421 is an apocalyptic number.

It is an amenable number.

623765421 is a deficient number, since it is larger than the sum of its proper divisors (348968979).

623765421 is a wasteful number, since it uses less digits than its factorization.

623765421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1215945 (or 1215939 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The square root of 623765421 is about 24975.2962144596. The cubic root of 623765421 is about 854.4246421492.

The spelling of 623765421 in words is "six hundred twenty-three million, seven hundred sixty-five thousand, four hundred twenty-one".