61428557 has 2 divisors, whose sum is σ = 61428558. Its totient is φ = 61428556.

The previous prime is 61428533. The next prime is 61428559. The reversal of 61428557 is 75582416.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57668836 + 3759721 = 7594^2 + 1939^2 .

It is a cyclic number.

It is not a de Polignac number, because 61428557 - 2²² = 57234253 is a prime.

Together with 61428559, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61428557.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61428559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30714278 + 30714279.

It is an arithmetic number, because the mean of its divisors is an integer number (30714279).

Almost surely, 2^61428557 is an apocalyptic number.

It is an amenable number.

61428557 is a deficient number, since it is larger than the sum of its proper divisors (1).

61428557 is an equidigital number, since it uses as much as digits as its factorization.

61428557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 67200, while the sum is 38.

The square root of 61428557 is about 7837.6372077304. The cubic root of 61428557 is about 394.5694330934.

The spelling of 61428557 in words is "sixty-one million, four hundred twenty-eight thousand, five hundred fifty-seven".