61557007 has 2 divisors, whose sum is σ = 61557008. Its totient is φ = 61557006.

The previous prime is 61556959. The next prime is 61557029. The reversal of 61557007 is 70075516.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61557007 - 2¹¹ = 61554959 is a prime.

It is a super-2 number, since 2×61557007² = 7578530221596098, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 61557007.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61557047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30778503 + 30778504.

It is an arithmetic number, because the mean of its divisors is an integer number (30778504).

Almost surely, 2^61557007 is an apocalyptic number.

61557007 is a deficient number, since it is larger than the sum of its proper divisors (1).

61557007 is an equidigital number, since it uses as much as digits as its factorization.

61557007 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7350, while the sum is 31.

The square root of 61557007 is about 7845.8273623627. The cubic root of 61557007 is about 394.8442626986.

The spelling of 61557007 in words is "sixty-one million, five hundred fifty-seven thousand, seven".