42909778 has 16 divisors (see below), whose sum is σ = 65940480. Its totient is φ = 20932576.

The previous prime is 42909767. The next prime is 42909781. The reversal of 42909778 is 87790924.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44550 + ... + 45502.

It is an arithmetic number, because the mean of its divisors is an integer number (4121280).

Almost surely, 2^42909778 is an apocalyptic number.

42909778 is a deficient number, since it is larger than the sum of its proper divisors (23030702).

42909778 is a wasteful number, since it uses less digits than its factorization.

42909778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1481.

The product of its (nonzero) digits is 254016, while the sum is 46.

The square root of 42909778 is about 6550.5555489592. Note that the first 4 decimals coincide. The cubic root of 42909778 is about 350.0946084377.

It can be divided in two parts, 4290977 and 8, that added together give a triangular number (4290985 = T₂₉₂₉).

The spelling of 42909778 in words is "forty-two million, nine hundred nine thousand, seven hundred seventy-eight".