147781551 has 4 divisors (see below), whose sum is σ = 197042072. Its totient is φ = 98521032.

The previous prime is 147781519. The next prime is 147781567. The reversal of 147781551 is 155187741.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 155187741 = 3 ⋅51729247.

It is not a de Polignac number, because 147781551 - 2⁵ = 147781519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (147781351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24630256 + ... + 24630261.

It is an arithmetic number, because the mean of its divisors is an integer number (49260518).

Almost surely, 2^147781551 is an apocalyptic number.

147781551 is a deficient number, since it is larger than the sum of its proper divisors (49260521).

147781551 is an equidigital number, since it uses as much as digits as its factorization.

147781551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49260520.

The product of its digits is 39200, while the sum is 39.

The square root of 147781551 is about 12156.5435465843. The cubic root of 147781551 is about 528.6968709646.

It can be divided in two parts, 1477 and 81551, that added together give a triangular number (83028 = T₄₀₇).

The spelling of 147781551 in words is "one hundred forty-seven million, seven hundred eighty-one thousand, five hundred fifty-one".