61815001 has 2 divisors, whose sum is σ = 61815002. Its totient is φ = 61815000.

The previous prime is 61814993. The next prime is 61815031. The reversal of 61815001 is 10051816.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36614601 + 25200400 = 6051^2 + 5020^2 .

It is a cyclic number.

It is not a de Polignac number, because 61815001 - 2³ = 61814993 is a prime.

It is not a weakly prime, because it can be changed into another prime (61815031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30907500 + 30907501.

It is an arithmetic number, because the mean of its divisors is an integer number (30907501).

Almost surely, 2^61815001 is an apocalyptic number.

It is an amenable number.

61815001 is a deficient number, since it is larger than the sum of its proper divisors (1).

61815001 is an equidigital number, since it uses as much as digits as its factorization.

61815001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 240, while the sum is 22.

The square root of 61815001 is about 7862.2516494958. The cubic root of 61815001 is about 395.3951096428.

Adding to 61815001 its reverse (10051816), we get a palindrome (71866817).

The spelling of 61815001 in words is "sixty-one million, eight hundred fifteen thousand, one".