21472742 has 4 divisors (see below), whose sum is σ = 32209116. Its totient is φ = 10736370.

The previous prime is 21472741. The next prime is 21472747. The reversal of 21472742 is 24727412.

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

It is a super-2 number, since 2×21472742² = 922157297997128, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21472741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5368184 + ... + 5368187.

It is an arithmetic number, because the mean of its divisors is an integer number (8052279).

Almost surely, 2^21472742 is an apocalyptic number.

21472742 is a deficient number, since it is larger than the sum of its proper divisors (10736374).

21472742 is a wasteful number, since it uses less digits than its factorization.

21472742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10736373.

The product of its digits is 6272, while the sum is 29.

The square root of 21472742 is about 4633.8690098016. The cubic root of 21472742 is about 277.9473271150.

The spelling of 21472742 in words is "twenty-one million, four hundred seventy-two thousand, seven hundred forty-two".