615228421 has 2 divisors, whose sum is σ = 615228422. Its totient is φ = 615228420.

The previous prime is 615228409. The next prime is 615228443. The reversal of 615228421 is 124822516.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 357625921 + 257602500 = 18911^2 + 16050^2 .

It is a cyclic number.

It is not a de Polignac number, because 615228421 - 2¹¹ = 615226373 is a prime.

It is a super-3 number, since 3×615228421³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (615228461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 307614210 + 307614211.

It is an arithmetic number, because the mean of its divisors is an integer number (307614211).

Almost surely, 2^615228421 is an apocalyptic number.

It is an amenable number.

615228421 is a deficient number, since it is larger than the sum of its proper divisors (1).

615228421 is an equidigital number, since it uses as much as digits as its factorization.

615228421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7680, while the sum is 31.

The square root of 615228421 is about 24803.7985195816. The cubic root of 615228421 is about 850.5087708450.

The spelling of 615228421 in words is "six hundred fifteen million, two hundred twenty-eight thousand, four hundred twenty-one".