61873991 has 2 divisors, whose sum is σ = 61873992. Its totient is φ = 61873990.

The previous prime is 61873943. The next prime is 61874003. The reversal of 61873991 is 19937816.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61873991 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61873921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30936995 + 30936996.

It is an arithmetic number, because the mean of its divisors is an integer number (30936996).

Almost surely, 2^61873991 is an apocalyptic number.

61873991 is a deficient number, since it is larger than the sum of its proper divisors (1).

61873991 is an equidigital number, since it uses as much as digits as its factorization.

61873991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 44.

The square root of 61873991 is about 7866.0022247645. The cubic root of 61873991 is about 395.5208447211.

The spelling of 61873991 in words is "sixty-one million, eight hundred seventy-three thousand, nine hundred ninety-one".