61664402 has 4 divisors (see below), whose sum is σ = 92496606. Its totient is φ = 30832200.

The previous prime is 61664401. The next prime is 61664417. The reversal of 61664402 is 20446616.

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., 51998521 + 9665881 = 7211^2 + 3109^2 .

It is not an unprimeable number, because it can be changed into a prime (61664401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15416099 + ... + 15416102.

Almost surely, 2^61664402 is an apocalyptic number.

61664402 is a deficient number, since it is larger than the sum of its proper divisors (30832204).

61664402 is a wasteful number, since it uses less digits than its factorization.

61664402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30832203.

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 61664402 is about 7852.6684636498. The cubic root of 61664402 is about 395.0737500492.

The spelling of 61664402 in words is "sixty-one million, six hundred sixty-four thousand, four hundred two".