206401251 has 16 divisors (see below), whose sum is σ = 314754048. Its totient is φ = 117854400.

The previous prime is 206401249. The next prime is 206401271. The reversal of 206401251 is 152104602.

It is not a de Polignac number, because 206401251 - 2¹ = 206401249 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (206401211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33286 + ... + 38996.

It is an arithmetic number, because the mean of its divisors is an integer number (19672128).

Almost surely, 2^206401251 is an apocalyptic number.

206401251 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

206401251 is a deficient number, since it is larger than the sum of its proper divisors (108352797).

206401251 is a wasteful number, since it uses less digits than its factorization.

206401251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7442.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 206401251 is about 14366.6715351887. The cubic root of 206401251 is about 590.9772667124.

Adding to 206401251 its reverse (152104602), we get a palindrome (358505853).

The spelling of 206401251 in words is "two hundred six million, four hundred one thousand, two hundred fifty-one".