61657943 has 2 divisors, whose sum is σ = 61657944. Its totient is φ = 61657942.

The previous prime is 61657931. The next prime is 61657951. The reversal of 61657943 is 34975616.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61657943 - 2⁶ = 61657879 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61657943.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61657993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30828971 + 30828972.

It is an arithmetic number, because the mean of its divisors is an integer number (30828972).

Almost surely, 2^61657943 is an apocalyptic number.

61657943 is a deficient number, since it is larger than the sum of its proper divisors (1).

61657943 is an equidigital number, since it uses as much as digits as its factorization.

61657943 is an evil number, because the sum of its binary digits is even.

The product of its digits is 136080, while the sum is 41.

The square root of 61657943 is about 7852.2571914068. The cubic root of 61657943 is about 395.0599556483.

The spelling of 61657943 in words is "sixty-one million, six hundred fifty-seven thousand, nine hundred forty-three".