81577403 has 2 divisors, whose sum is σ = 81577404. Its totient is φ = 81577402.

The previous prime is 81577381. The next prime is 81577411. The reversal of 81577403 is 30477518.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81577403 - 2¹⁶ = 81511867 is a prime.

It is not a weakly prime, because it can be changed into another prime (81577423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40788701 + 40788702.

It is an arithmetic number, because the mean of its divisors is an integer number (40788702).

Almost surely, 2^81577403 is an apocalyptic number.

81577403 is a deficient number, since it is larger than the sum of its proper divisors (1).

81577403 is an equidigital number, since it uses as much as digits as its factorization.

81577403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23520, while the sum is 35.

The square root of 81577403 is about 9032.0209809322. The cubic root of 81577403 is about 433.7005356256.

The spelling of 81577403 in words is "eighty-one million, five hundred seventy-seven thousand, four hundred three".