20740778 has 4 divisors (see below), whose sum is σ = 31111170. Its totient is φ = 10370388.

The previous prime is 20740777. The next prime is 20740781. The reversal of 20740778 is 87704702.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 13965169 + 6775609 = 3737^2 + 2603^2 .

It is not an unprimeable number, because it can be changed into a prime (20740777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5185193 + ... + 5185196.

Almost surely, 2^20740778 is an apocalyptic number.

20740778 is a deficient number, since it is larger than the sum of its proper divisors (10370392).

20740778 is a wasteful number, since it uses less digits than its factorization.

20740778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10370391.

The product of its (nonzero) digits is 21952, while the sum is 35.

The square root of 20740778 is about 4554.2044310725. The cubic root of 20740778 is about 274.7525178448.

The spelling of 20740778 in words is "twenty million, seven hundred forty thousand, seven hundred seventy-eight".