61878811 has 2 divisors, whose sum is σ = 61878812. Its totient is φ = 61878810.

The previous prime is 61878781. The next prime is 61878829. The reversal of 61878811 is 11887816.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61878811 is a prime.

It is not a weakly prime, because it can be changed into another prime (61878841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30939405 + 30939406.

It is an arithmetic number, because the mean of its divisors is an integer number (30939406).

Almost surely, 2^61878811 is an apocalyptic number.

61878811 is a deficient number, since it is larger than the sum of its proper divisors (1).

61878811 is an equidigital number, since it uses as much as digits as its factorization.

61878811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21504, while the sum is 40.

The square root of 61878811 is about 7866.3086006080. The cubic root of 61878811 is about 395.5311148467.

The spelling of 61878811 in words is "sixty-one million, eight hundred seventy-eight thousand, eight hundred eleven".