20280961 has 8 divisors (see below), whose sum is σ = 21492800. Its totient is φ = 19083600.

The previous prime is 20280941. The next prime is 20280979. The reversal of 20280961 is 16908202.

20280961 = 364² + 365² + ... + 477².

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20280961 - 2⁵ = 20280929 is a prime.

It is a super-2 number, since 2×20280961² = 822634758167042, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20280941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 666 + ... + 6403.

It is an arithmetic number, because the mean of its divisors is an integer number (2686600).

Almost surely, 2^20280961 is an apocalyptic number.

It is an amenable number.

20280961 is a deficient number, since it is larger than the sum of its proper divisors (1211839).

20280961 is a wasteful number, since it uses less digits than its factorization.

20280961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7239.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 20280961 is about 4503.4387971860. The cubic root of 20280961 is about 272.7069314492.

The spelling of 20280961 in words is "twenty million, two hundred eighty thousand, nine hundred sixty-one".