51435991 has 2 divisors, whose sum is σ = 51435992. Its totient is φ = 51435990.

The previous prime is 51435953. The next prime is 51435997. The reversal of 51435991 is 19953415.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51435991 - 2¹³ = 51427799 is a prime.

It is a super-2 number, since 2×51435991² = 5291322340304162, 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 51435991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51435997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25717995 + 25717996.

It is an arithmetic number, because the mean of its divisors is an integer number (25717996).

Almost surely, 2^51435991 is an apocalyptic number.

51435991 is a deficient number, since it is larger than the sum of its proper divisors (1).

51435991 is an equidigital number, since it uses as much as digits as its factorization.

51435991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24300, while the sum is 37.

The square root of 51435991 is about 7171.8889422522. Note that the first 3 decimals coincide. The cubic root of 51435991 is about 371.8967392701.

The spelling of 51435991 in words is "fifty-one million, four hundred thirty-five thousand, nine hundred ninety-one".