61405557 has 16 divisors (see below), whose sum is σ = 85898880. Its totient is φ = 38964800.

The previous prime is 61405541. The next prime is 61405579. The reversal of 61405557 is 75550416.

It is not a de Polignac number, because 61405557 - 2⁴ = 61405541 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61405537) 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, 1207 + ... + 11147.

It is an arithmetic number, because the mean of its divisors is an integer number (5368680).

Almost surely, 2^61405557 is an apocalyptic number.

It is an amenable number.

61405557 is a deficient number, since it is larger than the sum of its proper divisors (24493323).

61405557 is a wasteful number, since it uses less digits than its factorization.

61405557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10044.

The product of its (nonzero) digits is 21000, while the sum is 33.

The square root of 61405557 is about 7836.1697914223. The cubic root of 61405557 is about 394.5201822223.

The spelling of 61405557 in words is "sixty-one million, four hundred five thousand, five hundred fifty-seven".